Reading Main Idea Practice Questions
Read the passage below and answer question 1.
Americans have always been interested in their Presidents' wives. Many First Ladies have been remembered because of the ways they have influenced their husbands. Other First Ladies have made the history books on their own.
At least two First Ladies, Bess Truman and Lady Bird Johnson, made it their business to send signals during their husbands' speeches. When Lady Bird Johnson thought her husband was talking too long, she wrote a note and sent it up to the platform. It read, "It's time to stop!" And he did. Once Bess Truman didn't like what her husband was saying on television, so she phoned him and said, "If you can't talk more politely than that in public, you come right home."
Abigail Fillmore and Eliza Johnson actually taught their husbands, Millard Fillmore and Andrew Johnson, the thirteenth and seventeenth Presidents. A schoolteacher, Abigail eventually married her pupil, Millard. When Eliza Johnson married Andrew, he could not read or write, so she taught him herself.
It was First Lady Helen Taft's idea to plant the famous cherry trees in Washington, D. C. Each spring these blossoming trees attract thousands of visitors to the nation's capital. Mrs. Taft also influenced the male members of her family and the White House staff in a strange way: she convinced them to shave off their beards!
Shortly after President Woodrow Wilson suffered a stroke, Edith Wilson unofficially took over most of the duties of the Presidency until the end of her husband's term. Earlier, during World War I, Mrs. Wilson had sheep brought onto the White House lawn to eat the grass. The sheep not only kept the lawn mowed, but provided wool for an auction sponsored by the First Lady. Almost $100,000 was raised for the Red Cross.
Dolly Madison saw to it that a magnificent painting of George Washington was not destroyed during the War of 1812. As the British marched toward Washington, D. C., she remained behind to rescue the painting, even after the guards had left. The painting is the only object from the original White House that was not burned.
One of the most famous First Ladies was Eleanor Roosevelt, the wife of President Franklin D. Roosevelt. She was active in political and social causes throughout her husband's tenure in office. After his death, she became famous for her humanitarian work in the United Nations. She made life better for thousands of needy people around the world.
1. What is the main idea of this passage?
A. The Humanitarian work of the First Ladies is critical in American government.
B. Dolly Madison was the most influential president's wife.
C. Eleanor Roosevelt transformed the First Lady image.
D. The First Ladies are important figures in American culture.
E. The First Ladies are key supporters of the Presidents.
Read the passage below and answer question 2.
Of the many kinds of vegetables grown all over the world, which remains the favorite of young and old alike? The potato, of course.
Perhaps you know them as "taters," "spuds," or "Kennebees," or as "chips," "Idahoes," or even "shoestrings." No matter, a potato by any other name is still a potato- the world's most widely grown vegetable. As a matter of fact, if you are an average potato eater, you will put away at least 100 pounds of them each year.
That's only a tiny portion of the amount grown every year, however. Worldwide, the annual potato harvest is over 6 billion bags. Each bag contains 100 pounds of potatoes, some of them as large as four pounds each. Here in the United States, farmers fill about 400 million bags a year. That may seem like a lot of "taters," but it leaves the United States a distant third among world potato growers. Polish farmers dig up just over 800 million bags a year, while the Russians lead the world with nearly 1.5 billion bags.
The first potatoes were grown by the Incas of South America, more than 400 years ago. Their descendants in Ecuador and Chile continue to grow the vegetable as high as 14,000 feet up in the Andes Mountains. (That's higher than any other food will grow.) Early Spanish and English explorers shipped potatoes to Europe, and they found their way to North America in the early 1600s.
People eat potatoes in many ways-baked, mashed, and roasted, to name just three. However, in the United States most potatoes are devoured in the form of French fries. One fast-food chain alone sells more than $1 billion worth of fries each year. No wonder, then, that the company pays particular attention to the way its fries are prepared.
Before any fry makes it to the people who eat at these popular restaurants, it must pass many separate tests. Fail any one of these tests and the potato is rejected. To start with, only Russet Burbank potatoes are used. These Idaho potatoes have less water content than other kinds, which can have as much as 80 percent water. Once cut into "shoestrings" shapes, the potatoes are partly fried in a secret blend of oils, sprayed with liquid sugar to brown them, steam dried at high heat, then flash frozen for shipment to individual restaurants.
Before shipping, every shoestring is measured. Forty percent of a batch must be between two and three inches long. Another 40 percent has to be over three inches. What about the 20 percent that are left in the batch? Well, a few short fries in a bag are okay, it seems.
So, now that you realize the enormous size and value of the potato crop, you can understand why most people agree that this part of the food industry is no "small potatoes."
2. What is the main idea of this passage?
A. Potatoes from Ireland started the Potato Revolution.
B. The average American eats 50 pounds of potatoes a year.
C. French fries are made from potatoes.
D. Potatoes are a key vegetable in America.
E. The various terms for potatoes have a long history.
Read the passage below and answer question 3.
What does the word "patent" mean to you? Does it strike you as being something rather remote from your interests? If it does, stop and think a moment about some of the commonplace things that you use every day, those objects that you take for granted as part of the world around you. The telephone, radio, television, automobile, and the 1,001 other things (even the humble safety pin) that enrich our lives today once existed only as ideas in the minds of men. If it had not been possible to patent their ideas and thus protect them against copying by others, these inventions might never have been fully developed to serve mankind.
If there were no patent protection there would be little incentive to invent and innovate, for once the details of an invention became known, hordes of imitators who did not share the inventor's risks and expenses might well flood the market with their copies of his product and reap much of the benefit of his efforts. The technological progress that has made America great would wither rapidly under conditions such as these.
The fundamental principles in the United States patent structure came from England. During the glorious reign of Queen Elizabeth I in England, the expanding technology was furthered by the granting of exclusive manufacturing and selling privileges to citizens who had invented new processes or tools-a step that did much to encourage creativity. Later, when critics argued that giving monopoly rights to one person infringed on the rights of others, an important principle was added to the patent structure: The Lord Chief Justice of England stated that society had everything to gain and nothing to lose by granting exclusive privileges to an inventor, because a patent for an invention was granted for something new that society never had before.
Another basic principle was brought into law because certain influential people in England had managed to obtain monopoly control over such age-old products as salt, and had begun charging as much as the people could tolerate. The public outcry became so great that the government was forced to decree that monopoly rights could be awarded only to those who created or introduced something really unique. These principles are the mainstays of the modern patent system in the United States.
In colonial times, patent law was left up to the separate states. The inconsistency, confusion, and unfairness that resulted clearly indicated the need for a uniform patent law, and the men who drew up the Constitution incorporated one. George Washington signed the first patent law on April 10, 1790, and less than four months later the first patent was issued to a man named Samuel Hopkins for a chemical process, an improved method of making potash for use in soapmaking.
In 1936 the Patent Office was established as a separate bureau. From the staff of eight that it maintained during its first year of operation, it has grown into an organization of over 2,500 people handling more than 1,600 patent applications and granting over 1,000 every week.
The Patent Office in Washington, D. C. is the world's largest library of scientific and technical data, and this treasure trove of information is open for public inspection. In addition to more than 3 million US patents, it houses more than 7 million foreign patents and thousands of volumes of technical literature. Abraham Lincoln patented a device to lift steam vessels over river shoals, Mark Twain developed a self-pasting scrapbook, and millionaire Cornelius Vanderbilt invented a shoe-shine kit.
A patent may be granted for any new and useful process, machine, article of manufacture, or composition of matter (a chemical compound or combinations of chemical compounds), or any distinct and new variety of plant, including certain mutants and hybrids.
The patent system has also helped to boost the wages of the American worker to an unprecedented level: he can produce more and earn more with the computer, adding machines, drill press or lathe. Patented inventions also help keep prices down by increasing manufacturing efficiency and by stimulating the competition that is the foundation of our free enterprise system.
The decades of history have disclosed little need for modification of the patent structure. United States patent laws, like the Constitution from which they grew, have stood the test of time well. They encouraged the creative processes, brought untold benefits to society as a whole, and enabled American technology to outstrip that of the rest of the civilized world.
3. What is the main idea of this passage?
A. The patent system encourages free enterprise.
B. The Constitution protects the patent system.
C. The patent system in England has been influential in American patent development.
D. Patents are important tools for inventors.
E. Patented inventions protect the inventor, free enterprise, and the creative process.
Read the passage below and answer question 4.
Most people think that it's fine to be "busy as a beaver." Little do they know. Beavers may work hard, but often they don't get very much done.
Beavers are supposed to be great tree cutters. It is true that a beaver can gnaw through a tree very quickly: A six-inch birch takes about 10 minutes. But then what? Often the beaver does not make use of the tree. One expert says that beavers waste one out of every five trees they cut.
For one thing, they do not choose their trees wisely. One bunch of beavers cut down a cottonwood tree more than 100 feet tall. Then they found that they could not move it.
In thick woods, a tree sometimes won't fall down. It gets stuck in the other trees. Of course, the beaver doesn't think to cut down the trees that are in the way. So a good tree goes to waste.
Some people think that beavers can make a tree fall the way they want it to. Not true. (In fact, beavers sometimes get pinned under a falling tree.) When beavers cut a tree near a stream, it usually falls into the water, but they do not plan it that way. The fact is that most trees lean toward the water to start with.
Now what about dam building? Most beaver dams are wonders of engineering. The best ones are strongly built of trees, stones, and mud. They are wide at the bottom and narrow at the top.
Beavers think nothing of building a dam more than 200 feet long. One dam in Montana was more than 2,000 feet long. The largest one ever seen was in New Hampshire: it stretched 4,000 feet, and made a lake large enough to hold 40 beaver homes.
So beavers do build good dams. But they don't always build them in the right places. They just don't plan. They will build a dam across the widest part of the stream. They don't try to find a place where the stream is narrow. So a lot of their hard work is wasted.
Beavers should learn that it's not enough to be busy. You have to know what you're doing, too. For example, there was one Oregon beaver that really was a worker. It decided to fix a leak in a man-made dam. After five days of work it gave up. The leak it was trying to block was the lock that boats go through.
4. What is the main idea of this passage?
A. Beavers may be hard-working animals, but they don't always choose the most efficient mechanisms.
B. Beavers are excellent dam builders.
C. New Hampshire was the site of the largest beaver dam.
D. Beavers are well-developed tree cutters.
E. Beavers are poor surveyors of aquatic environments in some cases.
Read the passage below and answer question 5.
The raisin business in America was born by accident. It happened in 1873 in the San Joaquin Valley of California. Many farmers raised grapes in this valley. That year, just before the grape harvest, there was a heat wave. It was one of the worst heat waves ever known. It was so hot that the grapes dried on the vines. When they were picked, California had its first raisin crop.
People were surprised to find how good raisins were. Everybody wanted more. So the San Joaquin farmers went into the raisin business. Today, of course, they do not let the grapes dry on the vines. They treat them with much more care.
In late August the grapes start to ripen. They are tested often for sweetness. The growers wait until the sugar content is twenty-one percent. Then they know the grapes are ripe enough to be picked.
Skilled workers come to the vineyards. They pick the grapes by hand in bunches. The workers fill their flat pans with grapes. They gently empty the pans onto squares of paper. These squares lie between the long rows of vines. They sit in the sun.
Here the grapes stay while the sun does its work. It may take two weeks or longer. The grapes are first dried on one side. When they have reached the right color, they are turned to dry on the other side. The grapes are dried until only fifteen percent of the moisture is left. Then they have turned into raisins.
The raisins are rolled up in the paper on which they have dried. Trucks take them from the fields. They are poured into big boxes called sweatboxes. Each box holds 160 pounds of raisins. Here, any raisins that are too dry take moisture from those that have too much. After a while, they are all just moist enough.
The big boxes are trucked next to the packaging plant. They are emptied onto a conveyor belt that shakes the raisins gently. This knocks them from their stems. A blast of air whisks the stems away. The water bath is next. Then the plump brown raisins have a last inspection. They are again checked for moisture and sugar. Then they go on a belt to packing machines. Here they are poured into packages, which are automatically weighed and sealed. The raisins are now ready for market.
5. What is the main idea of this passage?
A. The creation of raisins in America was an accident.
B. The process of raisin development requires multiple steps.
C. Raisins on the grocery store shelf undergo a brief fermentation process.
D. Raisins are cleaned thoroughly at the packing plant.
E. California has been the leader in American raisin development.
Read the passage below and answer question 6.
In 1976, Sichan Siv was crawling through the jungle, trying to escape from Cambodia. By 1989, however, Siv was working in the White House in Washington D. C., as an advisor to the President of the United States. How did this strange journey come about?
Like millions of Cambodians, Siv was a victim of a bloody civil war. One of the sides in this war was the Cambodian government. The other was a group called the Khmer Rouge. When the Khmer Rouge won the war, the situation in Cambodia got worse. Many people were killed, while others were forced into hard labor. Sometimes entire families were murdered.
Siv came from a large family that lived in the capital of Cambodia. After finishing high school, Siv worked for a while with a Cambodian airline company. Later, he taught English. After that, he took a job with CARE, an American group that was helping victims of the war.
Siv had hoped to leave Cambodia before the Khmer Rouge took over the country. Unfortunately, he was delayed. As a result, he and his family were taken from their homes and forced to labor in rice fields. Eventually, Siv managed to escape. He rode an old bicycle for miles, trying to reach Thailand where he would be free and safe. For three weeks, he slept on the ground and tried to hide from the soldiers who were looking for him. Caught at last, he was afraid he would be killed. Instead, he was put into a labor camp, where he worked 18 hours each day without rest. After several months, he escaped again, and this time he made it. The journey, however, was a terrifying one. After three days of staggering on foot through mile after mile of thick bamboo, Siv finally made his way to Thailand.
Because he had worked for an American charity group, Siv quickly found work in a refugee camp. Soon he was on his way to the United States. He arrived in June of 1976 and got a job-first picking apples and then cooking in a fast-food restaurant. Siv, however, wanted more than this: he wanted to work with people who, like himself, had suffered the hardship of leaving their own countries behind. Siv decided that the best way to prepare for this kind of work was to go to college. He wrote letters to many colleges and universities. They were impressed with his school records from Cambodia, and they were impressed with his bravery. Finally, in 1980, he was able to study at Columbia University in New York City. After finishing his studies at Columbia, Siv took a job with the United Nations. He married an American woman and became a citizen. After several more years, he felt that he was very much a part of his new country.
In 1988, Siv was offered a job in the White House working for President Ronald Reagan's closest advisors. It was a difficult job, and he often had to work long hours. However the long hard work was worth it, because Siv got the opportunity to help refugees in his work.
6. What is the main idea of this passage?
A. Persistence and courage are global ideas.
B. Siv covered a large area during his life.
C. Siv persevered to escape from Cambodia.
D. Siv overcame numerous challenges to come to America and help others.
E. Siv persevered to become an American citizen.
Read the following passage and answer question 7.
When you want to hang the American flag over the middle of a street, suspend it vertically with the blue field (called the union) to the north and east-west street. When the flag is displayed with another banner from crossed staffs, the American flag is on the right. Place the staff of the American flag in front of the other staff. Raise the flag quickly and lower it slowly and respectfully. When flying the flag at half-mast, hoist it to the top of the pole for a moment before lowering it to mid-pole. When flying the American flag with banners from states or cities, raise the nation's banner first and lower it last. Never allow the flag to touch the ground.
7. What is the main idea of this passage?
A. The American flag is the symbol of American freedom.
B. The American flag has fifty stars.
C. Placing the American flag inappropriately will draw government intervention.
D. American flag should be flown differently in certain situations.
E. The flag should be lowered quickly and respectfully.
Read the following passage and answer question 8.
What if someone told you about a kind of grass that grows as tall as the tallest trees? A grass that can be made as strong as steel? A grass from which houses, furniture, boats, and hundreds of other useful things can be made? A grass that you would even enjoy eating? Would you believe that person? You should, for that grass is bamboo, the "wood" of 1,001 uses.
Bamboo may look like wood, but it is part of the family of plants that includes wheat, oats, and barley. It is a kind of grass. This grass is not just a material for making useful products. Young bamboo is eaten, often mixed with other vegetables, in many Asian foods.
Bamboo grows in many parts of the world. In the United States it grows in an area from Virginia west to Indiana and south to Florida, Louisiana, and Texas. Most bamboo, however, is found in warm, wet climates, especially in Asia and on the islands of the South Pacific Ocean.
In most Asian countries, bamboo is nearly as important as rice. Many Asians live in bamboo houses. They sit on bamboo chairs and sleep on bamboo mats. They fence their land with bamboo and use it to cage their chickens and pigs.
Bamboo is used to build large buildings as well as homes. When it is glued in layers, it becomes as strong as steel. On some islands in the South Pacific, bamboo is even used for water pipes. This extraordinary material has many other uses. It is used to make musical instruments such as flutes and recorders. Paper made from bamboo has been highly prized by artists for thousands of years.
Bamboo is light and strong, and it bends without breaking. It is cheap, floats on water, almost never wears out, and is easy to grow. Nothing else on earth grows quite so fast as bamboo. At times you can even see it grow! Botanists have recorded growths of more than three feet in just 24 hours! Bamboo is hollow and has a strong root system that almost never stops growing and spreading. In fact, only after it flowers, an event that may happen only once every 30 years, will bamboo die.
There are more than 1,000 kinds of bamboo. The smallest is only three inches tall and one-tenth of an inch across. The largest is more than 200 feet in height and seven inches in diameter. No wonder, then, that the lives of nearly half the people on earth would change enormously if there were no longer any bamboo. No wonder, too, that for many people, bamboo is a symbol of happiness and good fortune.
8. What is the main idea of this passage?
A. Bamboo has at least 2,000 uses.
B. Bamboo grows at an amazing rate and is found primarily in Asia.
C. Bamboo is an amazing grass that can be used in multiple ways.
D. There are at least 1,000 types of bamboo.
E. Bamboo could be considered a flower in some cases.
Read the following passage and answer question 9.
Every year since 1986, some of the world's most daring runners have gathered in the desert of Morocco. They are there to take part in one of the most difficult races in the world. The Marathon of the Sands, as it is called, covers over 125 miles of desert and mountain wilderness. The runners complete the course in fewer than seven days, and they run with their food, clothing, and sleeping bags on their backs.
The Marathon of the Sands was founded in 1986 by Patrick Bauer. His idea was to give the runners, who come from all over the world, a special kind of adventure. Most of the runners in this race have found that they form deep friendships with the other runners during their days and nights in the desert. Facing terrible heat and complete exhaustion, they learn much about themselves and each other.
For most of the runners, however, the challenge of the race is the main reason for coming. On the first day, for example, they run 15 miles across a desert of sand, rocks, and thorny bushes. Few runners finish the day without blistered and raw feet. Because they are allowed less than nine quarts of water during each day of the race, they also suffer from a lack of water. Most of all, they are exhausted when they arrive at the campsite for the night.
The second day, the runners awaken at 6:00 a.m. Within a few hours, it is 100 degrees Fahrenheit, but the runners do not hesitate. They must cover 18 miles that day. That night, they rest. They must be ready for the next day's run.
On the third day, the runners must climb giant sand dunes-the first they have faced. Dust and sand mix with the runners' sweat. Soon their faces are caked with mud. After 15 miles of these conditions, the runners finally reach their next camp.
The race continues like this for four more days. The fourth and fifth days are the worst. On the fourth day, the runners pass through a level stretch and a beautiful, tree-filled oasis, but then, on this and on the next day, they cross more than 21 miles of rocks and sand dunes. The temperature soars to 125 degrees Fahrenheit, and many runners cannot make it. Helicopters rush fallen runners to medical help. Runners who make it to the end of the fifth day know that the worst is over.
On the sixth day, heat and rocks punish the racers terribly. In the Valley of Dra, the wind picks up and, as the desert heat is thrust against them with great force, they grow more and more exhausted.
The seventh day is the last, with only 12 miles to be covered. The dusty, tired, blistered runners set out at daybreak. Near the finish line, children race along with the runners, for everybody has caught the excitement. The ones who have run the whole marathon know they have accomplished what most people could not even dream of. "During the hard moments," says one contestant who has raced here twice, "I'd think, 'Why am I here?' Then I'd realize I was there to find my limits."
9. What is the main idea of this passage?
A. The Marathon of the Sands race tests the limits of human endurance.
B. The runners run at their own paces.
C. The race causes the strong to stumble and the weak to not finish.
D. The seventh day is the hardest day of the race.
E. Every runner runs the race to find their human limits.
Read the following passage and answer question 10.
High in the Andes Mountains in Peru stands the ancient city of Machu Picchu. No one knows why this great city was built, nor is it likely that anyone will ever know. Nevertheless, the deserted city of Machu Picchu is important for what it reveals about the ancient Inca people of South America.
The Incas once ruled a great empire that covered a large part of the South American continent. The empire was more than 500 years old when the first Spanish explorers, looking for gold, went to that continent in the 16th century.
The Incas were an advanced people. They were skillful engineers who paved their roads and built sturdy bridges. They plowed the land in such a way that rains would not wash away valuable soil, and dug ditches to carry water into dry areas for farming.
Even though they did not know about the wheel, the Incas were able to move huge stone blocks-some as heavy as 10 tons-up the sides of mountains to build walls. The blocks were fitted so tightly, without cement of any kind, that it would be impossible to slip a knife blade between them! The walls have stood firm through great storms and earthquakes that have destroyed many modern buildings.
The Incas were great artists, too. Today, Incan dishes and other kinds of pottery are prized for their wonderful designs. Because both gold and silver were in great supply, the Incas created splendid objects from these precious metals.
While it is true that the Incas had no written language, they kept their accounts by using a system of knotted strings of various lengths and colors. The sizes of the knots and the distances between them represented numbers.
At its height, the Incan Empire included as many as 30 million people. The emperor ruled them with an iron hand. He told his subjects where to live, what to plant, how long they should work, and even whom they could marry. Because he owned everything, the emperor gave what he wished when he wished-and in the amount he wished-to his people.
In 1533, Spanish explorers led by Francisco Pizarro murdered the emperor of the Incas. Earlier, the heir to the Incan empire had also been killed. The Incas, who had always been entirely dependent on their emperor, now had no recognized leader. The Spaniards easily conquered the empire and plundered its riches.
Have the Incas disappeared from South America? Not at all. In Peru alone, once the center of that great empire, 80 percent of the 20 million people are descendants of the Inca people. Evidence of the Incan empire can be found in many other places in South America as well. Tourists can even visit Machu Picchu. The remains of this ancient city still stand high in the mountains of Peru, an awesome tribute to this once powerful empire.
10. What is the main idea of this passage?
A. The Incas once inhabited the ancient city of Machu Picchu.
B. Peru was the primary country of the Incas.
C. The Incan Empire can be found in ancient cities and was plundered by the Spanish.
D. Spanish conquerors destroyed the Incan empire in the 13th century.
E. Machu Picchu was the capital of the Incan empire.
Answers and Explanations
1. D: The passage describes actions of various First Ladies as examples of their importance in American culture. That they are key supporters of the Presidents (E) is not the main idea because the first paragraph states some First Ladies are remembered for influencing their husbands, while others "...have made the history books on their own." Not all First Ladies are described here as doing humanitarian work (A). No one First Lady is singled out as most important [(B), (C)].
2: D: The main idea is the importance of potatoes in America. It never mentions Ireland or any Potato Revolution (A). (B) is both incorrect-the passage states 100 lbs., not 50-and regardless of accuracy, is a detail, not the main idea. Readers already know French fries are made from potatoes (C), a detail the passage assumes. Several various terms for potatoes are mentioned in the second paragraph, but their history (E) is never discussed.
3. E: All three benefits of patents-inventor protection, free enterprise, and the creative process-are given equal importance in the passage. The other four choices each accurately identify individual ideas in the passage, but none incorporates all three parts of the main idea.
4. A: Only this choice identifies the main idea, that beavers are hard-working but not always efficient. Each of the other choices identifies one detail included in the passage, not the main idea.
5. B: The multiple steps required in the process are outlined throughout the passage. The introductory statement that the industry began by accident (A) is a detail, not the main idea. Shelf fermentation (C) is never mentioned. A water bath is mentioned, not thorough cleaning (D), and is a detail, regardless. California is only mentioned as the location of the first raisin crop but never identified as raisin development's leader (E).
6. D: The passage focuses on the many challenges overcome by the subject, Siv, in particular, rather than mentioning any global nature of his persistence and courage (A) or the size of the area he covered (B). His perseverance to escape (C) is true, but only part of the main idea, not mentioning his desire to help others. His attaining American citizenship is mentioned, but his perseverance was not for this (E), but for escaping Cambodia and helping other refugees.
7. D: The passage instructs how to fly the flag in different situations. It never mentions the flag's symbolism (A) or its number of stars (B), or any government intervention (C). It states the flag should be lowered slowly, not quickly (E).
8. C: The many uses of bamboo, and the fact it is a grass, are the main focus. "1,001 uses" is a non-literal colloquial expression meaning a great many; the passage never states factually that bamboo has at least 2,000 (A). Bamboo's growth rate and its location in many parts of the world, especially Asia (B), and the number of types (D), and the fact that it occasionally flowers (E), are details supporting/informing the main idea.
9. A: Testing human endurance limits is illustrated in this description of a punishing marathon. It never mentions runners running at their own paces (B). The race's challenges, and many not finishing (C) are details informing the main point. The seventh/last day is not the hardest (D); the fourth and fifth are identified as worst. (Regardless of accuracy, this is also a detail, not the main idea.) One, not every (E), runner is quoted as competing "to find my limits."
10. C: This choice best summarizes the passage's main points. Choice (D) incorrectly identifies the 13th century instead of the 16th century. The passage never indicates that Machu Picchu was the capital of the Incan empire (E). Answers (A) and (B) are details in support of the main idea.