Susan: Can’t you come in and have tea now, Peter?
Peter: Not yet, dear. I must water the garden first.
Susan: Do you have to water it now?
Peter: I’m afraid I must. Look at it! It’s terribly dry.
Susan: What a nuisance!（真讨厌）
Peter: Last summer it was very dry, too. Don’t you remember? I had to water it every day.
Susan: Well, I’ll have tea by myself.
Susan: That was quick! Have you finished already?
Peter: Yes, dear. Look out of the window.
Susan: Good heaven! It’s raining. That means you needn’t water the garden.
Peter: That was a pleasant surprise. It means I can have tea, instead.
1．Can't you come in and have tea now, Peter?彼得，你现在能进来喝茶吗？
这是否定疑问句，表示邀请。请参见 Lessons 77～78语法部分。
2．Don't you remember?你不记得了吗？
3．don't need to= needn't。
表示“不必”，是 must和 have to的一般现在时否定式。
4． a pleasant surprise,意想不到的好事，令人惊喜的事。
mean (meant, meant)
must, have to和 needn't
这3个词都表示必要性。在前面已对 must和 have to介绍过。
must是情态助动词，而have to是普通动词，二者在肯定句中一般可以互换，表示不可逃避的义务或责任。must更带有说话人的主观色彩，而have to则更强调客观要求和外界影响。
I shall have to leave London tomorrow.
I had to stop smoking because it was forbidden in my company.
如果我们用 must来提问，则只能用needn't来表达否定的回答。 needn't 还可以理解为have to的否定回答。needn't (don't need to)和 don't have to都表示不必要；而 mustn't却表示绝对禁止，在说话人看来根本没有选择余地。请看例句：
You mustn't turn left.
六、lesson 126 练习答案
1 Does she have to decide immediately?
She doesn't have to decide immediately.
2 Must she decide immediately?
She needn't decide immediately.
3 Do we have to take a taxi?
We don't have to take a taxi.
4 Must we take a taxi?
We needn't take a taxi.
1 I have to telephone him, too.
2 Mary has to wait for him, too.
3 Jim has to meet her ,too.
4 Tom and Mary have to travel by ship, too.
1 Do you really have to telephone him?
2 Does Mary really have to wait for him?
3 Does Jim really have to meet her?
4 Do Tom and Mary really have to travel by ship?