[单选题]额定电压是指变压器,它应与所连接的输变电线路()电压相符合。
A.相电压;
B.线电压 ;
C.最大电压

Many people are worried about what television has done to the generation of American children who have grown up watching it. For one thing, recent studies show that TV weakens the ability to imagine. Some teachers feel that television has taken away the child’s ability to form mental pictures in his own mind, resulting in children who cannot understand a simple story without pictures. Secondly, too much TV too early usually causes children to be removed from real-life experiences. Thus, they grow up to be passive watchers who can only respond to action, but not start doing something actively. The third area for such a worrying situation is the serious dissatisfaction frequently expressed by school teachers that children show a low patience for the pains in learning. Because they have been used to seeing results of all problems in 30 or 60 minutes on TV, they are quickly discouraged by any activity that promises less than immediate satisfaction. But perhaps the most
A. are frightened
B. feel satisfied
C. become annoyed
D. think it’s real