问题
选择题
– What’s wrong with your ipad2? The sound ____is not clear.
--Yes. It has been broken for some time.
A．come out
B．coming out
C．to come out
D．came out
答案
答案：B
考查非谓语动词。逻辑主语sound与come out之间是主动关系，而come out本身也是不及物动词词组，故不能用过去分词作后置定语。而句子的谓语动词是is，故不能再出现谓语动词，D排除。故选B.