If your mother wants to tell you something, she uses words. Birds can not talk as we do. But some birds can make sounds to warn their young of danger. They have their own ways to make the young birds do certain thing.
The jackdaw is a kind of blackbirds that lives in Europe. Jackdaws live together in flocks. ( 群) Yong jackdaws do not know their enemies. When an older jackdaw sees a dog , it makes a loud tattling (格格响的)sound.The young birds know this sound means an enemy is nearby. The sounds warns them to know their enemy.
If a young jackdaw is in a dangerous place, a jackdaw parent flies over him from behind.The parent bird flies low over the young bird’s back, the parents’ tail feathers move quickly from side to side, It is trying to say, “ Follow me.”
At the same time , the parent calls out, “ Key-aw ,Key-aw.” The parent means, “ Fly home with me.” The young bird then follows the older one home.
Young jackdaws do not have to learn what certain sounds mean.They know the meaning of these sounds from the time they hatch.
小题1:The jackdaw lives in _____ .
A．Europe
B．Australia
C．America
D．Africa小题2:When an old jackdaw sees a dog , it _____ .
A．calls out “Follow me .”
B．makes a loud sound
C．flies away
D．fights the dog .小题3: Parent jackdaw can use their tail feathers to ______ .
A．ask their young to follow them
B．play a game with the young
C．tell the meal time
D．give a warning of a fire小题4:The story tells much about _____ .
A．the danger of jackdaws.
B．in which mother can talk to their children.
C．the way jackdaws warn their young of danger.
D．how the jackdaws are living.小题5: Which of the following does this story lead you to believe ?
A．All animal parents can talk to their young.
B．Dogs are the most dangerous enemies for jackdaws.
C．Young jackdaws know the meaning of their parents’ sound when they grow older .
D．Some birds can give certain information to one another.
，其中
，n为整数．确定n的值时，要看把原数变成a时，小数点移动了多少位，n的绝对值与小数点移动的位数相同．当原数绝对值＞1时，n是正数；当原数的绝对值＜1时，n是负数．
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