can能否与beable to互换使用

Question

如题所述

Answer 1

1.can表示“能力”时，和beable to相当，许多场合都可以互相替换。但当叙述过去经过一番努力才能完成的事情或前面有特殊说明，表示你有能力时，只能用be able to。
【正】Can you speak anyforeign languages?
你会说外语吗？
【正】Are you able tospeak any foreign languages?
你会说外语吗？
【误The fire spread thebuilding quickly but everybody could escape.
【正The fire spread thebuilding quickly but everybody was able to escape.
大火迅速蔓延到整幢大楼，但大家都逃了出来。
【正The fire spread thebuilding quickly but everybody managed to escape.
大火迅速蔓延到整幢大楼，但大家都想法逃了出来。
2.beable to 比can有更多形式。
No onecould answer the question.
没人能回答这个问题。（这里could可用was able to代替）
When hegrows up, he will be able to support his family.
他长大后就能养家了。
Frank isill. He hasn't been able to go to school for one week.
弗兰克病了，已经一周没去上学了。
I'msorry for not being able to help you in time.
对不起，不能及时帮你的忙。
3.could经常和动词see,hear, smell, taste, feel, remember, understand等连用。
When wewent into the house, we could smell something burning.
当我们走进屋子时，我们闻到什么东西烧焦了。（不用was able to）
Shespoke in a very low voice, but I could understand what she said.
虽然她讲话的声音很低，但我还是明白了她说的话。
4.在谈论说话时发生的动作，用can，不用be able to。
【误】Look! I'm able toswim.
【正】Look! I canswim. 看，我会游泳了！
5.在用used to谈论过去用能力做某事，但现在失去了这个能力时，我们用be able to。
如：I used to be ableto play the violin.
6.在谈论将来有能力做某事。我们用will be able to。
如：After only a fewlessons, you will be able to understand basic Spanish.
7.在其它动词may,might,would,want或hope后，用be ableto.
如：He might be able tofix your car.
Youshould be able to taste the difference.
I wanther to be able to use a computer.