---Dad, must we wait until the light becomes green?---Yes, I’m afraid we ______. That’s the traffic rule.

---Must we donate our pocket money to the poor right now?---No, you _______. You can think it over and do it before Friday.

No one ______ be more generous; he has a heart of gold.

Any information one wants to know about the coming National Games in Shenyang, just call 024- 62347788. It ________ be simpler. 

---Is that Lucy’s sister, Lily?---No, it _______ be her. She has gone to English.