Question

Billions of locusts (蝗虫) are moving through farms and fields in the East African countries of Ethiopia, Kenya and Somalia.

Locusts are grasshoppers. Normally grasshoppers don't travel in groups and so they do little harm. But when there are lots of them, their bodies and behavior change. That's when they become locusts. Locusts travel in huge groups, laying eggs along the way, which produce even more locusts. In a single day, a small swarm (群) of the insects can eat as much food as 35,000 people do.

The locust swarms in Ethiopia and Somalia are the worst in 25 years. These locusts are desert locusts. They began swarming about six months ago. By moving with the winds, desert locusts can travel up to 90 miles a day or more.

Locust swarms are more common when heavy rains follow a long dry period. The insects lay their eggs in the wet ground. This season, East Africa has had its heaviest rainy season in 40 years.

When the insects swarm, one square kilometer of land can hold as many as 150 million locusts. There are 700 square kilometers of land covered by the insects in Kenya alone.

The insects are a threat to lives in the region, where food is already in short supply. Already many farmers who keep animals are struggling because locusts have eaten out the plants the animals usually live on.

In East Africa, farmers have been shooting into the air or making noises in the fields, but that doesn't work against so many insects. Experts say that spraying pesticides (杀虫剂) over large areas from airplanes is the only way to reduce the number of insects. The UN has released (释放) $10million to help deal with the locust problem. The UN says about $70 million is needed to truly control the locusts with pesticides.

1.Which is TRUE about locusts?

A.Normally they don't travel in groups.

B.A small swarm of locusts eat a lot of food a day.

C.They lay eggs in the wind.

D.They do little harm to the plants.

2.East Africa has got the locust problem because ________.

A.the land is too dry to grow crops B.farmers pull out all the grass there

C.poor people love to eat locusts as food D.it has too much rain after the dry season

3.How many locusts are there in Kenya?

A.About 150,000,000 B.About 700,000,000

C.About 1, 850. 00,000 D.About 105,000,000,000

4.According to the passage, a "threat" probably can ________.

A.bring good luck to people B.make people live a happy life

C.cause danger in the future D.help keep more animals

5.We can infer from the last paragraph that ________.

A.farmers are trying to scare the insects off

B.spraying pesticides can't solve the locust problem

C.the UN thinks the locust problem isn't serious

D.East Africa has required no more help so far

Answer

1.B

2.D

3.D

4.C

5.A

【解析】

文章是一篇说明文。介绍了蝗虫的危害。

1.

判断正误题。根据第2段“Locusts travel in huge groups”可知蝗虫成群传播，故A错误。根据第4段“The insects lay their eggs in the wet ground.”可知蝗虫把卵产在潮湿的地面上，故C错误。根据倒数第2段“locusts have eaten out the plants”可知蝗虫吃植物，对植物而言，蝗虫是灭顶之灾，故D错误。根据第2段“In a single day, a small swarm (群) of the insects can eat as much food as 35,000 people do.”可知一天之内，一小群昆虫可以吃掉35,000人的食物。故B正确。故选B。

2.

细节理解题。根据第4段“Locust swarms are more common when heavy rains follow a long dry period. This season, East Africa has had its heaviest rainy season in 40 years.”可知大雨过后很长一段时间，蝗虫群更常见。而东非经历了40年来最大的雨季。故选D。

3.

数字计算题。根据第5段“When the insects swarm, one square kilometer of land can hold as many as 150 million locusts. There are 700 square kilometers of land covered by the insects in Kenya alone.”可知一平方公里的土地可以容纳多达1.5亿只蝗虫。仅在肯尼亚，就有700平方公里的土地被昆虫覆盖。即1.5亿×700=1050亿。故选D。

4.

词义推测题。根据倒数第2段“The insects are a threat to lives in the region, where food is already in short supply. ”可知该地区粮食已经短缺，而且蝗虫吃粮食，所以“威胁着”该地区的生命，是很危险的。故选C。

5.

推理判断题。根据最后一段“In East Africa, farmers have been shooting into the air or making noises in the fields,”可知在东非，农民们一直在向空中射击或在田野中发出声音，如此做是为了吓退蝗虫。故选A。