老师们希望学生独立完成作业.Teachers their students their homework . 题目和参考答案——青夏教育精英家教网—

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老师们希望学生独立完成作业。

Teachers __________ their students _______ _________ their homework _______ ________ .

prefer; to do; by themselves

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Upon __________ home, he was arrested by the police.

A．arriving B．arrived C．arrive D．to arrive

Although men and women have been growing crops for thousands of years, they have not always had enough to eat. Even today, many people in the world go hungry, and even die of hunger. If we are to grow enough for everybody, we have to grow more crops and better crops.

Plants need the right food in order to grow. In particular, they need three chemical substances (物质) in the soil: nitrogen (氮), phosphorus (磷) and potassium (钾). They also need smaller amounts of other chemical substances like calcium. If there is too little of any of these substances in the soil, plants can’t grow well.

When a plant grows, it takes up these basic substances from the soil and builds them into itself. If we remove the plant from the soil and use it for food, we are taking some of these substances away, and this means that future plants will find less of them in the soil. In time, the soil would become too poor for plants to grow in it at all.

To prevent this we must put basic substances back. One way of doing this is putting manure (肥料) on the soil. This contains the remains of plants that have been eaten, and, if we add it to the soil, we are returning some of the basic substances. In Europe and in Japan, manure from animals has for long been used in this way. Unfortunately much of the animal waste in India is used as fuel because there is not enough wood to burn. This means there is less manure for the crops.

Even when we use manure, we can not put back into the soil more of the basic substances than have been taken out. Often the soil does not have enough of them in the first place, and so we must provide extra supplies. We can use chemical fertilizers (化肥). Experiments in India have shown that, if we use a fertilizer containing a mixture of nitrogen and phosphorus, we get half as much rice again from the crops on any one piece of land.

72. According to the passage, how many methods are introduced to improve the soil?

A. One. B. Two. C. Three. D. Four.

73. The underlined word “this” (in Paragraph 4) refers to the fact that ____________.

A. the soil would become too poor for plants to grow in it at all

B. we are taking some substances away from the soil

C. the plant takes up these essential substances from the soil

D. even today many people in the world go hungry

74. To make sure that the soil has enough basic substances, people can _____________.

A. remove plants from the soil

B. provide the soil with extra supplies

C. plant as many plants as possible

D. stop planting in the soil

75. The passage is mainly about _____________.

A. why more food is needed

B. how to grow better crops

C. the fact that people have not always enough to eat

D. the essential substances that plants need

What have happened to you? I haven’t ________ _________ you for a long time.

你最近怎样了？我已经很久没收到你的来信了。

Flight CZ3254 from Guangzhou to Beijing __________________ (take off) at 8:20 am. and ________________ (get to) Beijing at 10:55 am.

英国和法国被海水分开。

England ______ ___________ ________ France by sea.

He was excited that he couldn’t speak a word.

= He was ________ excited ________ say a word.

I used to be a very delightful girl. I guess no human being could have passed ______ childhood.

A. a happy B. a happier C. the happier D. the happiest

Over 60,000 people died _____ the earthquake in Wenchuan, Sichuan Province.

A. with regard to B. as a consequence of C. in the course of D. on the ground of

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