题目内容

A model or an experiment in a science class can help students see things which would          remain hidden.

A.otherwise            B.still                      C.thus                       D.therefore

 

 

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Plants, like animals, are subject to diseases of various kinds.It has been estimated that some 30,000 different diseases attack our economic plants; forty are known to attack corn, and about as many attack wheat.The results of unchecked plant disease are all too obvious in countries which have marginal food supplies.The problem will soon be more widespread as the population of the world increases at its frightening rate.Even in countries which are now amply fed by their agricultural products there could soon be the major crops; the resulting famines(饥荒) could kill millions of people, and the resulting hardship on other millions could cause political upheavals(动乱) disastrous to the order of the world.

Some plants have relative immunity to a great many diseases, while others have a susceptibility to them.A blight (萎菌病) may be but a local infection easily controlled; on the other hand it can attack particular plants in a whole region or nation.An example is the blight which killed virtually every chestnut tree in North America.Another is the famous potato blight in Ireland in the last century.As a result of that, it was estimated that one million people died of starvation and related ailments.

Plant pathologists have made remarkable strides in identifying the pathogens of the various diseases.Bacteria may invade a plant through an infestation of insect parasites carrying the pathogen.A plant can also be inoculated by man.Other diseases might be caused by fungus which attacks the plant in the form of a model or smut or rust.Frequently such a primary infection will weaken the plant so that a secondary infection may result form its lack of tolerance.The symptoms(症状) shown may cause an error in diagnosis, so that treatment may be directed toward bacteria(细菌) which could be the result of a susceptibility caused by a primary virus infection.

How many diseases are known to attack wheat?

       A.Around 30000          B.Forty           

       C.Around 29960           D.Around 40

Unchecked plant disease won't result in_______.

A.food shortages in poor country      B.food shortages in rich country

    C.increase of world population   D.disaster in world politics

What is the main idea of the second paragraph?

A.Some plants have relative immunity to a great many diseases.

B.Some other plants have a susceptibility to a great many diseases.

C.The tolerance of a particular plant changes as the growing conditions change.

D.A blight can be a national infection.

According to the passage, some plant diseases can__________.

A.infect people          

B.be prevented by inoculation(接种疫苗)

C.be prevented by killing insects      

D.be prevented by improving the growing conditions

Which of the following won’t cause plant disease ?   

A.Fungus     B.Mold C.Smut D.Rust

阅读下面的短文,请根据短文后的要求答题(注意问题后的字数要求)

[1] Do you ever wish you were as thin as a model or as strong as your favorite football player? Maybe you wish you were taller or just shaped(塑形) a little differently. Those thoughts are a natural part of growing up. How can you feel better about your body?

[2] Firstly, learning what you can and can’t change about your body is part of growing up .It can be hard to accept. But when people accept the way they look, they often feel happier.

[3] Eating healthy foods can make people feel better about their bodies. Why?­­ Because ________will make you full of energy and keep your body working just the way it should.

[4]Watching TV and playing computer games can be fun, but it doesn’t do much for your body because your body stays still(静止的). Those are called sedentary(需要久坐的)activities because you sit while you do them.

[5] But when you move your body—by playing, dancing, taking part in sports, or even cleaning your room – you exercise your muscles(肌肉).When you exercise a muscle, it gets stronger and stronger. And when you have strong muscles, you can do whatever you want to do.

[6] People feel better about their bodies when their bodies can do whatever they want them to do. So climb a hill, jump rope, ride a bike, swim in a pool ,run up the stairs, or even do the hula – and enjoy all your body can do!

1.What’s the main idea of this passage? (no more than 10 words)

_______________________________________________________________________________

2.Translate the underlined sentence into Chinese.

_______________________________________________________________________________

3.Fill in the blank in paragraph 3 with proper words. (no more than 3 words)

_______________________________________________________________________________

4.Why do watching TV and playing computer games aren’t good for us according to paragraph4? (no more than 15 words)

_______________________________________________________________________________

5.What will your muscles be after you exercise them? (no more than 10 words)

_______________________________________________________________________________

 

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