Question

【题目】According to the air traffic rules, you ______ switch off your mobile phone before boarding.

A . ought to B. may C. can D. would

Answer 1

【答案】A

【解析】

试题分析：句意：根据空中交通规则的要求，你应该在登机前关掉你的手机。ought to应该，应当。故选A。