Leaves are nature’s food factories. Plants take water from the ground through their roots. They take a gas called carbon dioxide (CO2) from the air. Plants use sunlight to turn water and CO2 into glucose（葡萄糖）.Glucose is a kind of sugar. Plants use glucose as food for energy to grow. The way plants turn water and CO2 into glucose is called photosynthesis (光合作用).That means “putting together with light .” A chemical called chlorophyll helps make photosynthesis happen. Chlorophyll is green. It gives plants their green colour. As summer ends and autumn comes, the days get shorter and shorter. This is how the trees “know” to begin getting ready for winter.
During winter, there is not enough light or water for photosynthesis .The trees will rest, and live on the food they have stored during the summer. They begin to close their food-making factories. The green Chlorophyll disappears from the leaves. Then, we begin to see yellow and orange colours. A few of these colors stay in the leaves all the time. We just can’t see them in the summer, because they are covered up by the green Chlorophyll.
Red and purple colors we see in leaves are made mostly in the autumn. In some trees, like maples, glucose is stored in the leaves after photosynthesis stops. Sunlight and the cool nights of autumn turn this glucose into red. The brown color of trees like oaks is made from wastes left in the leaves.
The underlined word “chlorophyll” in the first Para means in Chinese.
A 叶绿素 B 氧气 C 胡萝卜素 D 蛋白质
The way is called photosynthesis.
A. plants get CO2 from the air
B. plants take water from the ground
C. plants turn water and CO2 into glucose.
D. Plants use glucose as food for energy to grow.
The gas called carbon dioxide is from the
A ground B roots C air D sunlight
Which of the following is not true?
A. when autumn and winter come, the days get shorter and shorter.
B. During winter trees rest and live on the food they store during the summer.
C. During winter small amounts of yellow and orange colors are kept in the leaves all the time.
D. Trees begin to stop making food in summer.
科目：高中英语 来源： 题型：阅读理解
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
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科目：高中英语 来源： 题型：阅读理解
The tea gardens in Sri Lanka are actually large estates(种植园). The best tea usually comes from plants grown on high grounds, the cool hilltops with rows and rows of tea plants. The plants are about one metre apart. The plant is often pruned so that it remains only 60 to 90 centimetres high. Pruning is important because it encourages the growth of tender shoots, or young leaves. It is from these shoots that the best tea is got.
Practically all the tea pickers are women. The estates prefer to employ women pickers because they are more careful. Their thin fingers can easily remove the twin leaves and new shoots from the plant, which are the parts used for processing(加工) tea. The pickers carry large baskets into which they throw their pickings. A skilled worker can harvest between 9 to 14 kilogrammes of tea leaves a day. Usually new shoots can be picked from the plants about every ten or fifteen days.
Processing tea shoots into the familiar dry tea leaves requires great care and skill .There are various methods of processing depending on the type of tea required .For black tea ,the young green leaves are first spread out o shelves to dry. This process removes much of its water and the leaves become soft. After this ,the leaves are passed through heavy rollers .This operation will press the leaves for juices which give the tea both its colour and taste .Then the leaves are spread out on floors and left to ferment （发酵）under wet conditions. Fermentation develops the rich taste of black tea .The fermented leaves are then dried with a hot-air blower until they become rolled-up black leaves .The final step is to sort and grade them before the black tea is ready for sale to countries all over the world.
68．In the first paragraph ,the word “pruning” means .
A．regular cutting of the plants
B．frequent watering
C．regular use of chemicals
D．growing the plants high in the mountain
69．One of the reasons why women are employed to do the picking is that .
A．they work harder than men do in the picking
B．they can throw their pickings more easily into the baskets
C．their fingers fit them better for the job.
D．they can more easily find the twin leaves.
70．How many processing steps are mentioned in the last paragraph?
A．Three. B．Four. C．Five. D．Six.
71．What is the writer’s purpose in writing the passage?
A．To introduce various methods of tea processing.
B．To persuade readers to buy tea from Sri Lanka.
C．To tell a story that had happened in the tea gardens.
D．To inform readers of tea growing ,picking and processing.
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科目：高中英语 来源：2007年高考辽宁卷英语试题 题型：阅读理解
Most rain forests lie close to the equator(赤道),where the climate is often mild and there are long hours of sunshine.The warmth of the land heats the air above,causing it to rise and tiny drops of water to fall as rain.The rainfall can reach at least 98 inches a year.This wet,warm world with plenty of sunlight is perfect for plants to grow,so the trees grow fast with green leaves all the year round.The trees themselves also have an effect on the climate.They gather water from the soil and pass it out into the air through their leaves.The wet air then forms clouds,which hang over the treetops like smoke.These clouds protect the forest from the daytime heat and night-time cold of nearby deserts,keeping temperatures fit for plant growth.
Rain forests slightly farther away from the equator remain just as warm,but they have a dry season of three months or more when little rain falls.Tree leaves fall during this dry season and new leaves grow when the wet season or monsoon(雨季) begins.Thus these areas are known as the “monsoon forest”.
Another type of rain forest grows on tropical mountains.It is often called the “cloud forest” because clouds often hang over the trees like fog.
The rain forest is the ideal place for the growth of many different trees.Most of them depend on animals to eat their fruits and spread their seeds.When the fruits are eaten,the seeds inside them go undamaged through animals’ stomachs and are passed out in their droppings.The seeds lying on the forest floor then grow into new trees.
【小题1】The climate of the rain forests near the equator is _______.
| A．mild,wet and windy | B．hot,rainy and foggy |
| C．hot,wet and cloudy | D．warm,wet and sunny |
| A．tree leaves are green all the time in the monsoon forest |
| B．there is a dry season in the cloud forest on tropical mountains |
| C．clouds help the plants in the rain forest near the deserts to grow |
| D．the formation of climate in the rain forest has little to do with the trees |
| A．animals | B．droppings | C．fruits | D．winds |
| A．a travel guide | B．a story book |
| C．a technical report | D．a geography book |
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科目：高中英语 来源：2011届四川省南充高中高三第七次月考英语卷 题型：填空题
短文改错(共l0小题；每小题1.5分，满分l5分)
此题要求改正所给短文中的错误。对标有题号的每一行作出判断：如无错误，在该
行右边横线上画一个勾(√)；如有错误(每行只有一个错误)，则按下列情况改正：
此行多一个词：把多余的词用斜线(＼)划掉，在该行右边横线上写出该词，并也用斜线划掉。
此行缺一个词：在缺词处加一个漏字符号(∧)，在该行右边横线上写出该加的词。
此行错一个词：在错的词下划一横线，在该行右边横线上写出改正后的词。
注意：原行没有错的不要改。
Have you ever been bored with the busy life in the city？If so， 1．___________
have glimpse of the primary forest with me. The breathtaking 2．___________
scenery make you forget everything when you’re exploring what 3．___________
the forest has to offer. With thousands of trees surrounded 4．___________
you，you will feel like to floating on the green ocean. Under the 5．___________
leaves are all kinds of flowers，peacefully and shy. And a 6．___________
variety of birds were singing happily in the trees. While you’re 7．___________
enjoying the scenery on the ground，watching out for the sky！ 8．___________
It will give your eye a feast. Wandering alone in the forest， 9．___________
we will have the feeling of returning to nature. 10．___________
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科目：高中英语 来源：2014届黑龙江哈尔滨第四中学高三上期第二次月考英语卷（解析版） 题型：单项填空
____ the temperature down day by day, the leaves are turning yellow.
A. For B. With C. Because D. As
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