Question

【题目】The doctor looks tired and sleepy ____he stayed up late to look after his patients yesterday.

A. ifB. becauseC. whileD. so that

Answer 1

【答案】B

【解析】

句意：医生看起来又累又困，因为他昨天熬夜照顾病人。A. if如果；B. because因为；C. while当……的时候； D. so that为了，目的。根据下文he stayed up late to look after his patients yesterday.可知这里是表示原因，用because,根据题意，故选B。