The boy is an _____.[ ]
A. English
B. American
C. Chinese
D. America boy
答案：B
软盘置为写保护状态后，则该盘片_____ 。
A．能防止病毒入侵
B．不能防止病毒人侵
C．用杀毒软件对它进行杀毒
D．若有病毒也不至于扩散
Don't _____ the radio. The baby is sleeping. [ ]
A. turn on
B. turn off
C. turn down
D. turn up
