题目内容

_____ how plants were related was a complex and strange thing before Linnaeus developed his system.

A.
To having shown
B.
Shown
C.
Show
D.
Showing

D
showing为动名词，后带一个宾语从句，构成动名词短语作句子的主语。

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Animals can move from place to place, but plants cannot. When an animal is under attack, it can run away or fight back.. Plants certainly cannot run away, and they lack teeth and claws. But plants can defend themselves by using both physical and chemical means.

Some plants have their own ways to keep animals away. For example, the leaves of the holly plant have sharp spines (刺) that discourage grass-eating animals. Holly leaves on lower branches have more spines than leaves on upper branches. This is because the lower leaves are easier for most animals to reach.

Some plants, such as the oak tree, have thick and hard leaves that are difficult for animals to eat. Some grasses may contain a sandy material; eating such grasses wears down the animal's teeth.

Many plants also have chemical defenses. Some plants produce chemicals that taste bitter or cause an unpleasant reaction. Some plants may fight against an attack by increasing the production of these chemicals. When a caterpillar (毛虫) bites a tobacco leaf, the leaf produces a chemical messenger. This messenger sends to the roots the information to produce more nicotine. The higher levels of nicotine discourage the caterpillar.

Many plants depend on both physical and chemical defenses. A certain plant in China, for

instance, has prickly (多刺的) leaves, and each prickle contains poisonous venom (毒液) A single experience with this kind of plant will teach an animal to stay away from it in the future.

The holly plant has more spines on the lower leaves because most animals________.

A. are not tall enough B. like the lower leaves only

C. are not clever enough D. can get the lower leaves easily

To defend themselves, oak trees use________.

A. chemical means B. physical means

C. bitter chemicals D. sandy materials

How does tobacco protect itself against an attack from a caterpillar?

A. Its leaves fight against the attack by physical means.

B. Its roots send a messenger to discourage the caterpillar.

C. Its roots increase the production of nicotine when it is attacked.

D. Its leaves produce poisonous sand to drive the caterpillar away.

What would be the best title for this passage?

A. Plants and Animals B. How Plants Defend Themselves

C. Attacks and Defenses D. How Animals Eat Plant Leaves

The effects of air pollution on natural conditions have been a disturbing problem for many years. Some scientists hold the view that the air inside houses may be more dangerous than the air outside. It may even be one hundred times worse.
Most scientists agree that every modern house has some kind of indoor pollution, which can cause a person to feel tired, to suffer eye pain, headache and other problems. Believe it or not, some pollutants can cause breathing diseases of blood and even cancer.
What made us feel relieved is that there’s growing concern about the problem now. It is true that when builders began constructing houses and offices they did not want to waste energy. To do this they built buildings that prevented or limited the flow of air between inside and outside. For the same purpose, man-made building materials were employed to build houses, which are now known to let out some harmful gases.
Facing the serious challenge, scientists have been searching for a way to handle the problem. To everyone’s delight, they discovered a natural pollution control system for building—green plants, though they do not really know how plants control air pollution. Scientists suppose that a plant’s leaves absorb or take in the pollutants and in exchange gives out oxygen through its leaves and tiny organizations on its roots. Therefore they recommend that all buildings should have one large plant or several small plants inside for every nine square meters of space. Because studies indicate that different plants absorb different chemicals, the most effective way to clean the air is to use different kinds of plants. In conclusion, having green plants inside your house can make it a prettier and healthier place. Why not try?
【小题1】Which of the following statements is TRUR?

A．Outside air pollution is more harmful than the air inside.

B．Scientists have discovered how plants control air pollution

C．Indoor air pollution may cause diseases including cancer.

D．Only large plants can absorb harmful gases indoors.

【小题2】According to scientists, some kind of indoor pollution can be found in ________.

A．every old building

B．every modern house

C．all kinds of houses

D．all kinds of offices

【小题3】What does the underlined part “To do this” refer to in Para3?

A．To build houses and offices

B．To limit the air flow inside

C．To use man-made materials

D．In order not to waste energy

【小题4】The reason why we should use different kinds of plants to clean the air is that ___.

A．plants can drive out all kinds of pollutants indoors

B．plants can absorb different harmful indoor chemical

C．plants can take in all pollutants inside and outside

D．plants may give out more oxygen than people need

Not all vegetables need lots of sunshine. Mark Hoffman and his wife own a bed-and-breakfast guesthouse in rural Kempton, Illinois. They often serve their guests fresh products from the garden.
The Hoffmans have been growing food and flowers for twenty-five years. For almost ten of those years, Mr. Hoffman has been experimenting and working with shade (阴凉) plantings. He says, “The bottom line here is that most plants will produce more in full sun. But if you do not have full sun, there are other choices.”
For example, he grows tomatoes near oak trees. Oak trees can produce a lot of shade. But Mr. Hoffman says his tomato plants grow as long as they get five hours’ direct sunshine a day, especially morning sun. Not only does this go against the traditional advice that tomatoes need six, eight, even twelve hours’ full sun a day. It also shows how plants and tree roots can share nutrients and water.
Mr. Hoffman says plants with wider leaves seem to do better in shady environments. He also found that his potatoes did better partly in shade than in full sun.
Moving them out of the sun helped control an insect problem. Mr. Hoffman does not use pesticide (农药). Instead, he planted the potatoes in the shade, especially on the east side of the tree. The potatoes get morning sun, but they are shaded during the hottest part of the day. Some insects dislike shade, and the hottest part day is when they do the worst of their damage.
Time of day, sun intensity (强度), shadows from trees, walls and buildings all influence how much sunlight falls on plants. And people interested in shade planting should also remember something else. The term “shade” can describe different amounts of darkness. It can even mean different things in different parts of the world.
【小题1】How many hours of sunshine are enough to keep tomato plants growing in Hoffman’s garden?

A．five hours a day	B．Six hours a day
C．Eight hours a day	D．Twelve hours a day

【小题2】From the passage we can know that ______ .

A．plants with wider leaves produce more in full sun.

B．as a matter of fact, plants don’t need to grow in full sun.

C．the more sunshine plants get, the more they will produce

D．plants with wider leaves grow better in shadows

【小题3】All of the following can influence how much sunlight falls on plants EXCEPT ______.

A．length of day time

B．brightness of the sun

C．changes of the season

D．shadows

【小题4】 Which of the following can best describe Mr. Hoffman?

【小题5】We may read the passage on a website in the section of ______.

Animals can move from place to place, but plants cannot. When an animal is under attack, it can run away or fight back. Plants certainly cannot run away, and they lack teeth and claws. But plants can defend themselves by using both physical and chemical means.

Some plants, such as the oak tree, have thick and hard leaves that are difficult for animals to eat. Some grasses may contain a sandy material; eating such grasses wears down the animal's teeth.

Many plants depend on both physical and chemical defenses. A certain plant in China, for instance, has prickly (多刺的) leaves, and each prickle contains poisonous venom (毒液). A single experience with this kind of plant will teach an animal to stay away from it in the future.

1.The holly plant has more spines on the lower leaves because most animals________.

A．are not tall enough B．like the lower leaves only

C．are not clever enough D．can get the lower leaves easily

2.To defend themselves, oak trees use________.

A．chemical means B．physical means

C．bitter chemicals D．sandy materials

3.How does tobacco protect itself against an attack from a caterpillar?

A．Its leaves fight against the attack by physical means.

B．Its roots send a messenger to discourage the caterpillar.

C．Its roots increase the production of nicotine when it is attacked.

D．Its leaves produce poisonous sand to drive the caterpillar away.

4.What would be the best title for this passage?

A．Plants and Animals B．How Plants Defend Themselves

C．Attacks and Defenses D．How Animals Eat Plant Leaves

Most scientists agree that every modern house has some kind of indoor pollution, which can cause a person to feel tired, to suffer eye pain, headache and other problems. Believe it or not, some pollutants can cause breathing diseases of blood and even cancer.

What made us feel relieved is that there’s growing concern about the problem now. It is true that when builders began constructing houses and offices they did not want to waste energy. To do this they built buildings that prevented or limited the flow of air between inside and outside. For the same purpose, man-made building materials were employed to build houses, which are now known to let out some harmful gases.

Facing the serious challenge, scientists have been searching for a way to handle the problem. To everyone’s delight, they discovered a natural pollution control system for building—green plants, though they do not really know how plants control air pollution. Scientists suppose that a plant’s leaves absorb or take in the pollutants and in exchange gives out oxygen through its leaves and tiny organizations on its roots. Therefore they recommend that all buildings should have one large plant or several small plants inside for every nine square meters of space. Because studies indicate that different plants absorb different chemicals, the most effective way to clean the air is to use different kinds of plants. In conclusion, having green plants inside your house can make it a prettier and healthier place. Why not try?

1.Which of the following statements is TRUR?