Question

If you are afraid of the dark，it’s not a big deal．It’s perfectly normal to feel afraid After all，animals do too. “Fear matters，”says Karen Warkentin，an ecologist．“It’s a good thing，” she adds, “because fear makes you do things that keep you alive.”

Like kids，many animals experience fear and they respond to the feeling in variety of ways．A frightened turtle pulls its head and legs inside its shell．A small fish will swim away when a big，hungry fish approaches．

Some animals respond to fear in ways you might not expect．The first example is that the fear of being eaten can scare some frogs right out of their eggs. Warkentin made the surprising discovery while studying red—eyed tree frogs in Costa Rica.

In this species，female frogs attach jellylike clumps（果冻一样的块状物）of their eggs to the undersides of leaves．The leaves hang on branches that dangle（悬挂）over ponds．After they hatch from the eggs，the tadpoles（蝌蚪）then fall into the water，where they eventually grow into adult frogs.

Tree frog eggs usually grow for 6 days before hatching．If they sense that a hungry snake is about to attack，however，they can hatch up to 2 days ahead of schedule. As the snakes are unable to swim，by falling into the water early，the tadpoles can escape.

If hatching early helps protect red—eyed tree frogs from snakes，you might wonder why their eggs don’t always hatch sooner．It turns out that hatching early brings its own danger．Once tadpoles land in the water，hungry fish and other animals like to eat them too．Staying in their eggs for a full 6 days，then，allows frog embryos（胚胎）to grow big and strong．This extra growth improves their chances of surviving in the water．

1.It can be inferred from the passage that fears      .

A.help animals grow bigger and stronger

B.are less common among young animals

C.help animals move a lot to fit the environment

D.are more or less important in order for animals to survive

2.We are told in the passage that tree frogs        .

A.face danger both inside their eggs and in the water

B.will grow fast if they fall into the water later

C.are surprisingly clever when inside their eggs

D.stay in their eggs longer if they are frightened

3.Why do the tadpoles hatch up to 2 days ahead of the schedule？Because

A.They like falling into the water early

B.They want to grow into adult frog

C.They sense a hungry snake is about to attack

D.Frog embryos can grow strong

4.What is the best title of the passage?

A.What is Fear B.Why do we feel afraid

C.You feel afraid，animals do too D.Fear is a good thing

5.What do you think would be discussed in the following paragraph?

A.Further explanations as to why tree frogs hatch ahead of schedule．

B.How the unborn frogs know when a snake is about to attack them．

C.Another example of animals that responds to fear in an unexpected way．

D.How tree frogs improve their chances of survival before falling into the water.

Answer

1.D

2.A

3.C

4.D

5.C

【解析】

本文是一篇科普说明文。文章叙述了人们和动物常见的一种现象就是恐惧。本文主要谈及的是恐惧是一种好事，然后举例论述这一观点，许多动物对于恐惧的反映是不同的，但是也有一些你想象不到的反映方式，然后短文以红眼树蛙为例，当它孵化蛋时，如果害怕遇到蛇的攻击提前孵化出来，掉到水里的蝌蚪能够逃离蛇的攻击。

1.推理判断题。根据文章第一段because fear makes you do things that keep you alive动物为了生存，恐惧或多或少是重要的。故选D。

2.细节理解题。根据文章第五段If they sense that a hungry snake is about to attack，however，they can hatch up to 2 days ahead of schedule. Once tadpoles land in the water，hungry fish and other animals like to eat them too．可知，树蛙在孵化期间害怕蛇的攻击，在水里害怕水里其他动物把蝌蚪吃掉，故选A。

3.细节理解题。根据文章第五段If they sense that a hungry snake is about to attack，however，they can hatch up to 2 days ahead of schedule. As the snakes are unable to swim，by falling into the water early，the tadpoles can escape.可知，如果它们感觉到一条饥饿的蛇即将攻击，它们可以提前2天孵化。故选C。

4.标题归纳题。根据网站第一段Fear matters，It’s a good thing级全文内容可知，文章主要叙述害怕是一种好事。故选D。

5.推理判断题。根据Some animals respond to fear in ways you might not expect．The first example is that the fear of being eaten can scare some frogs right out of their eggs.既然这是举例，有了第一个例子，那么它的后面必需还有例子，故选C。