Question

In spring, you may have seen white foam(泡沫) on a green tree or other plants. As a matter of fact, the foam is where young spittlebugs(吹沫虫) live. These insects are protected by the foam, and they usually don’t do much harm to the plants.

As we all know, in late summer, a mother spittlebug lays her eggs on the plant. The babies will hatch(孵化) in spring. After they come to the new world, they begin to eat juice from the plant. The babies eat more juice than their bodies need for food. The extra juice mixes with a special waste that the spittlebugs produce. When this fluid(液体) is released, it mixes with the air, forming bubbly foam.

What is so great about having a foam home? The space inside is so wet that it can keep the bugs’ soft bodies from drying out. And the foam tastes bad, so it keeps away most animals that would eat the bugs. Some birds will reach their heads through the foam to find the bugs. Wasps and ants might eat them, too. But most of the bugs stay safe inside the foam.

Once the bugs have grown into adults, they stop making foam. They leave their homes and jump from plant to plant in search of food. The adults look a little like tiny frogs. For this reason they are also called froghoppers.

If you see some foam on a plant, you might want to take a careful look inside. Gently push some of the foam aside with a small stick. Deep inside you may see a few insects eating plant juice. They might also be making more foam. Be sure to push the foam back after a moment to cover the insects and keep them safe. Soon the spittlebugs will grow up and leave their foam home. They will join the other insects in the grassland.

1.The eggs of spittlebugs_____.

A. are laid in late spring

B. have to pull through a winter before they hatch

C. are protected by mother spittlebugs all the time

D. will be eaten by ants

2.According to the passage, the white foam_____.

A. does much harm to the plant

B. protects the plant from being harmed

C. is where a mother spittlebug is living

D. is plant juice mixed with spittlebugs’ waste and the air

3.Which of the following is a function of a foam home?

A. Protecting the bugs from being eaten.

B. Helping the bugs find food.

C. Providing enough drinking water for the bugs.

D. Keeping the plant from drying out.

4.After the spittlebugs grow into adults, they______.

A. continue to make foam

B. take on a different look

C. begin to eat tiny frogs

D. begin to do harm to plants

Answer

1.B

2.D

3.A

4.B

【解析】

试题解析：本文讲述了寄居在泡沫上的吹沫虫是如何形成的和长大后的它们，以及泡沫对那些臭虫的保护作用。

1. we all know, in late summer, a mother spittlebug lays her eggs on the plant. The babies will hatch(孵化) in spring.”在夏末，吹沫虫的妈妈就会在植物上产卵，然后到冬天，这些卵就会孵化成小吹沫虫。由此可知，吹沫虫的卵在孵化前要渡过一个冬天。故选B。

2. extra juice mixes with a special waste that the spittlebugs produce. When this fluid(液体) is released, it mixes with the air, forming bubbly foam.”露珠与吹沫虫产生的废物混合起来，然后当这些液体释放出来时，它又会与空气中的水蒸气结合，因此形成了泡沫。因此可知，泡沫是由吹沫虫产生的废物和空气中的水蒸气混合形成的。故选D。

3. the foam tastes bad, so it keeps away most animals that would eat the bugs.”泡沫尝起来很不好，所以这就可以防范其它的动物去吃这些臭虫。因此可知，泡沫的一个功能之一就是保护臭虫被吃掉。故选A。

4. adults look a little like tiny frogs.”长大的吹沫虫看起来就像小的青蛙。因此可知在外表上，吹沫虫长大后和幼小时是有点不一样的。故选B。

考点：考查社科类短文。