Mustn't vs Don't have to

英文原文：

Hi guys, this is Kee from BBC Learning English. Today I'm going to tell you the differences between 'mustn't' and 'don't have to'.

Now 'must' and 'have to' are similar in meaning – they are both used to describe obligations. However, their negative forms are completely different in meaning.

We still use 'mustn't' to talk about obligations. For example:
'In the house, I mustn't wear shoes' – you know, to keep the house clean.

But don't have to does not describe obligations, so the choice is yours. For example, if your teacher said 'you don't have to do your homework', well then the choice is yours. You can say 'alright, I won't'.

中文翻译：

大家好，我是来自BBC Learning English的Kee。今天我将告诉您“mustn't”和“don't have to”的区别。

现在，“must”和“have to”的意思相似-它们都用于描述义务。然而，它们的否定形式在意义上完全不同。

我们仍然使用“mustn't”来谈论义务。例如：“在房子里，我不能穿鞋”-你知道，为了保持房子的清洁。

但是，“don't have to”并不描述义务，所以选择权在你手中。例如，如果你的老师说“你不必做你的家庭作业”，那么选择就在你手中了。你可以说“好的，我不做”。

测验：

1. You ____ recycle your waste, but it will be good for the environment.

A.don't have to 

B.mustn't

2. When visiting art galleries, you____touch the paintings on display.

A.don't have to 

B.mustn't

3. You____wear a costume at the Halloween party.

A.don't have to 

B.mustn't

4. You___ copy other students' homework – it's not right!

A.don't have to 

B.mustn't

答案：
1A

2B

3A

4B