can be able to区别是什么?
be able to 与can用法区别:
(1) be able to 强调通过努力而获得的能力,而can则强调自身已具有的能力。如:
She can sing the song in English. 她能用英语唱这首歌。
He will be able to sing this song in English in a few minutes, too. 几小时之后,他也能用英语唱这首歌。
(2) be able to 强调一种结果,而can只强调一种可能。如:
Luckily, he was able to escape from the big fire in the end. 幸运的是,他终于逃出了大火。
If he got here a few hours earlier, I could save him. 要是他早几小时来,我还能救他。
(3) be able to 可以有各种时态;而can只有一般现在和一般过去两种时态。如:
I could help you last night, but you didn't come. 昨天晚上我能帮你,而你又没来。
Can you see it there? 你能看见它在那儿吗?
He is / was / will be able to help you.他能帮你的忙。
(4) can可用于表示可能性,推测,允许等情况,而be able to通常不这样用。