be able to 是什么意思，请前辈帮造个句方便理解

是能够的意思，相当于can，但比can时态多。
如完成时：She had been able to send home regularly fifteen dollars a week to maintain the family.

与情态动词相连：
I ought to be able to live on my salary.
上述用法都无法用can替代。

be able to和can的不同点是:
be able to强调是后天性的能力
例
I am able to swim 说的是你经过训练后学会了游泳
I can swim 说的是你会游泳 可能是天生就会 也可能是训练后才会的

能够的意思~~和CAN的意思相近,但不相同~~BE ABLE TO强调能力~~
After the practice, I was able to swim.

是能够的意思 比如 I am able to swim. 我可以游泳
相当于can

be able to
v.
能, 会

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