Question

　　We all cry for water when we are thirsty. But do you know, in very hot, dry weather, plants also make very low sounds-as if they are crying out for help?

　　You see,in a plant's stem（莖）there are several hundred “water pipes （管道）”that bring water from soil all the way up to the leaves. When the ground turns dry, it becomes harder and harder for plants to do this.

　　In very hot days, plants have to get any water that it can. Scientist Robert Winter has found out that when plants can get no water, their “water pipes” snap （發出斷裂聲）. When that happens, the whole plant vibrates （振動） a little.

　　Robert knows that healthy, well-watered plants are quiet. He also knows that many insects （昆蟲）prefer attacking dry plants rather than healthy plants. How do the insects know which are healthy plants and which are not? Robert thinks that the insects may hear the plants crying and then they may come to kill it.

(1)There are many “water pipes”_________.

[　　]

A．in a plant's stem	B．in a plant's peel（果皮）
C．in a plant's bark（樹皮）	D．in the earth

(2)When plants can, ________, their “water pipes” snap.

[　　]

A．grow well	B．get no sunlight
C．have enough water	D．get no water

(3)When “water pipes”snap, the whole plant ________.

[　　]

A．keeps quiet	B．vibrates a little
C．gets well	D．makes very loud sounds

(4)Many insects like to attack ________.

[　　]

A．quiet plants

B．dry plants

C．healthy plants

D．well-watered plants

Answer 1

答案：A;D;B;B