Both Can and Could

Can和Could都是情态动情。一般来说，Could比Can更有礼貌（或者说更正式）。

CAN

The three main uses of Can are: 1) ability 2) possibility and 3) permission. However there are some other used of Can as we will see below.

Can的三种主要用法是：1) 能力 2) 可能性 3) 允许。但是正如我们下面将会看到的那样，Can也还有其它的一些用法。

1. To express ability 表示能力

Can means to be (physically) able to do something OR to know how to do something.

Can意思是（身体上）能够做某事或知道如何做某事

• Birds can fly. 鸟儿能飞。
• Elephants can't fly. 大象不能飞
• I can speak two languages. 我能说两种语言。

2. To express a possibility (in general) 表示（一般意思上的）可能性

This refers to a theoretical possibility.

这指的是理论上的可能性.

Note: we don't use can to talk about future possibilities. For this you would use may or might.

注意：我们不用can来谈论将来的可能性。而是用may或might.

• It can get cold there at night so take a jacket. 夜里会变冷，所以拿件夹克吧。
• I know you can win the competition. 我知道你能赢得比赛。
• Well, I think your car can be repaired, but it's not going to be cheap. 那么，我想你的车能修好，但不会太便宜。

3. To offer to do something for others 答应为其它人做某事

Can is used when you offer to help someone or to do something for them.

当你答应帮助某些人，或为他们做某事的时候，会用Can。

• You don't need to walk home. I can take you there if you like. 你不需要走回家。如果你愿意的话，我能载你到那。
• Can I carry your bags for you? 需要我为您提行李吗？

4. To ask for or give permission / To request something 要求或允许 / 请求某事

Can is used to ask for / request permission or to give permission.

Can用来请求许可或给出许可。

Note: Can't is used to refuse permission.

注意：Can't用来拒绝请求。

• You can use my umbrella, I don't need it right now. 你可以使用我的雨伞，我现在不需要它。
• Can I sit in that chair please? 请问我能坐那个椅子吗？
• Mary, you can play outside if you like. Mary，如果你愿意，可以在外面玩。
• Can I ask you a question? 我能问你个问题吗？
• You can't go to the park. It will still be wet from the rain last night.你不能去公园。昨天下了雨，地还没干。
• We can't leave the room until the assignment is completed. 在作业完成前，我们不能离开房间。

5. Can't: Something that is forbidden or not allowed

Can't: 某些被禁止或不允许的事情

• We cannot park the car next to this fire hydrant.我们不能在消防栓旁边停车。
• You can drive as fast as you want on the German motorways.在德国高速公路上，你想开多快就开多快。
• You can't smoke in the restaurant. 你不能在饭店抽烟。
• You cannot drive a car without a license.你不能无证驾驶小汽车。

6. Can't: when you are sure that something isn't true or something is surprising

• It can't be dark outside! It's only 4.30pm! 外面不会真的黑了吧，这才下午四点半。
• They can't have landed on the moon, I'm sure it's a hoax. 他们不可能登录了月球，我敢确定这就是个恶作剧

COULD

Could is similar to Can and often replaces Can in the past tense (though not always)

Could和Can类似，经常在过去时态中替代Can(虽然不是一定要替代）

1. To express ability in the past 表示过去的能力

• I could ride a horse when I was younger but now I can't. 在我小时侯能骑马，但现在不会了。
• She could juggle eight balls when she was only 10 years old.她10岁时就能同时玩8个球。
• He could read when he was three years old.当他3岁时就会读书了。

2. Polite word used to ask for permission or to request something (in the present) 当请求许可或某物时的礼貌词语（现在时）

• Could I please use your bathroom? 请问我能用您的浴室吗？
• Could we move on to the next topic now please?请问我们可以推进到下一个话题了吗？
• Could you pass me the salt please?请问您可以把盐递给我吗？
• I'm busy right now. Could you call back later?我现在在忙。您能一会再打过来吗？

3. General permission in the past 过去的一般许可

• In high school, we couldn't leave the classroom without a pass. 在高中，我们在未得到允许时不能离开教室。
• He couldn't go to the concert because his mother wouldn't let him.他不能去演唱会，因为他的妈妈不让他去。

4. A suggestion when asked what to do (choices and opportunities) 当问到做什么时的一个建议（选择和机会）

• He could try and fix it himself. 他可以试着自己修好它。
• We could go to the movies if you are interested. 如果你感兴趣的话，我们可以去看电影。

5. Couldn't: Sure that something is untrue

Couldn't: 确定某事是假的。

Just like can't, you can use couldn't when you are sure that something isn't true or real.

就像can't一样，当你确定某事不是真的时，可以用couldn't

• That couldn't be my cat meowing outside, it was hit by a car last week. 那不可能是我的猫在外面叫，它上星期被一辆车撞了。
• He couldn't have painted that. He has no artistic ability at all.他不可能画了那幅画。他一点艺术细胞也没有。

6. Could + have + past participle: To express a possibility in the past

Could + have + 过去分词：表示过去的一种可能性

To express that something was possible but did not happen.

表达了某些有可能但未发生的事情。

• We were lucky because it could have rained but it didn't. 我们是幸运的，因为本可能下雨但没下。
• Why did you do that? You could have broken your leg.为什么你那样做？你可能会弄伤你的腿的。

7. Could + have + past participle: Unrealised past ability

Could + have + 过去分词：未意识到的过去的能力

This is used to say that someone was able to do something, but they did not try to do it. Sometimes this is a form of criticism.

这用来表示：某人以前能做某事，但他们没有试着那样做。有时这是一种批评的形式。

• She
  could have married anyone she wanted to. 以前她本可以嫁给任何她想嫁的人。
• Why did you sit there doing nothing? You could have helped me. 你为什么坐那里啥也不做？你本可以帮帮我。

8. Could: A conditional form of Can

Could：条件语句中的Can。

Would + Can = Could. Note: Would be able to can replace could in the following examples.

Would + Can = Could. 注意：下面的例子里的Would be able to可以替代could

• If we had some oranges I could make you some fresh juice.如果我们有些桔子，我可以给你做新鲜的桔汁。
• I could write the letter if you told me what to include. 我可以写这个信件，如果你告诉我需要包括哪些内容的话。

Can vs Could Summary Chart

閱讀更多 寶寶學英語 的文章

關鍵字: Room S.H.E 电影梦工厂