Question

【题目】________you are at the post office, would you please help me post this letter?

A. Because B. Before C. Until D. While

Answer 1

【答案】D

【解析】句意：当你在邮局的时候，请你帮我把这封信邮走好吗？Because因为；Before在…之前；Until直到…时候；While当…时候。根据句意would you please help me post this letter可知，在邮局的时候才能去邮信，故应选D。