Question

9. —Dad,must we wait until the light becomes green?

—Yes,I'm afraid we       . That’s the traffic rule.

   A. can   B. may   C. have to   D. need

Answer 1

9. C

由“那是交通规则”可知，我们必须要等到灯变为绿色。

have to “不得不”强调客观上的要求。故选C。