Modal Verbs(10點)

你好，我尽量解释得详细点给你看咯。

Can 用来表达能力或才能，机会，请求或要求，给于允许，显示可能性/可能发生的事情或者不可能性/不可能发生的事情 (express ability or opportunity, to request or offer permission, and to show possibility or impossibility)。

请看以下的例子:-

1) I can ride a horse. (ability)
2) You can stay with my brother when you are in Paris. (opportunity)
3) She cannot stay out after 10 PM. (permission)
4) Can I have a glass of water? (request)
5) Any child can grow up to be president. (possibility)

Could 就用来表达可能性/可能发生的事情，它不只用来表达过去式的能力或才能，而且还能作出提议和请求或要求。“Could”也通常被用在一些表示条件的句子，跟那些“can”的表示条件的句子一样用。 (express possibility or past ability as well as to make suggestions and requests. "Could" is also commonly used in conditional sentences as the conditional form of "can")

1) Peter could be the one who stole the money. (possibility)
2) I could speak Chinese when I was a kid. (past ability)
3) You could spend your vacation in Malaysia. (suggestion)
4) Could I borrow your book? (request)
5) If I had more time, I could travel around the world. (conditional)

Must 跟 Have to 蛮相似的。但它们有一个很大的分别，那就是我们通常用 must 来给他人我们的意见，而我们则用 have to 来说某人有必务/需要/不得不去做的。

1) John is a really nice person. You must meet him. (I recommend this)
2) I have to work from 8.30 to 5.30 every day. (this is a fact, not an opinion)

Should 也是跟 Ought to 蛮相似的。但它们有一个分别，那就是
我们通常用 ought to 来表达比较强烈或有力的可能性/可能发生的事情，跟随着某些该得的东西或事情。

1) Alan ought to get the promotion. (It is expected because he deserves it)

Would 跟 May 可以说是很大的差别咯。
我们通常都会在我们想象某个情况或动作下用 Would 的。

1) It would be nice to buy a new car, but we cannot afford it. (we imagine it)
2) If I were president, I would cut the cost of education.

May 则是在说着某样东西或事情是个可能性/可能发生的事情，可能发生的动作或未来会发生的事情。

1) The story may be true. (= perhaps it is true)
2) Take an umbrella with you. It might rain later. (= perhaps it will rain)

希望我的解释够清楚，能让你明白。
也希望能帮到你咯。。。: )

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