（  ）13.Jane is in a hurry because the train to the airport leaves_____half an hour.

A.By

B.in

C.for

D.until

13.B【解析】此处in half an hour意为“半个小时以后”。句意：Jane很着急，因为去机场的火车半小时后出发。根据句意选B。

（  ）14.Jim_____his strict father，for he failed in the exam once again.

A.didn’t dare to see

B.not dare see

C.dared not to see

D.dare not saw

14.A【解析】dare既可作情态动词，也可作实义动词。作实义动词后跟不定式，作情态动词后跟动词原形。句意：Jim不敢见他严厉的父亲，因为他又一次考试不及格。

（  ）15.If you have any doubts about your health，you’d better  your doctor at once.

A.Convince

B.consult

C.avoid

D.affect

15.B【解析】convince“说服，信服”；consult“咨询，参考”；avoid“避免”；affect“影响”。句意：如果你对你的健康有疑问，最好咨询你的医生。