— 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

---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

用所给词的适当形式填空

1.We ______________________(not see) each other since last week.

2.The roller coaster moved at high speed and was very _____________(excite).

3.We _______________(wait)for the bus when a traffic accident happened.

4._______________(be) pollution a serious problem then?

5.All of us went on a school trip to South Hill except ____________(he) last week.