2015职称英语理工类A级阅读理解练习及答案(4)

　　When We Are Asleep

　　Dreams take the form of stories，but they may be strange and with incidents not connected，which make little sense. Dreams are seldom without people in them and they are usually about people we know. One estimate says that two-thirds of the cast of our dream dramas are friends and relations. Vision seems an essential part of dreams，except for people blind from birth. Sound and touch are senses also often aroused，but smell and taste are not frequently involved. In normal dreams，the dreamer may be taking part，or be only an observer. But he or she cannot control what happens in the dream.

　　16.Some people dream but cannot remember their dreams.

　　17.In an average night，males dream longer than females.

　　18.When we dream，there is less movement of electrical waves in our brains.

　　19.Babies dream less than older children.

　　20.Most dreams involve the people we played with when we were young.

　　21.We rarely smell things in dreams.

　　22.In a lucid dream we can use Morse code to communicate with others.