Shall we...？

建议：Shall we go to the cinema？

肯定回答：All right, OK, Good idea.

否定回答：I'm afraid not.

Why not...？

建议：Why not try again？

肯定回答：Great, that's a good idea.

否定回答：I'm afraid not.

What about...？

建议：What about going out for a walk？

肯定回答：That sounds wonderful.

否定回答：I'm not really interested.

You'd better...？

建议：You'd better stay at home.

肯定回答：OK, I'll stay at home.

否定回答：No, I'd rather not.

Let's...？

建议：Let's go swimming.

肯定回答：Yes, let's go swimming.

否定回答：I'm sorry, but I can't.

这些句子在日常对话中非常常见，用于表达各种建议。希望这些例子对你有所帮助。