abler , ablest
Someone who is able is very intelligent or very good at doing something.
one of the brightest and ablest members of the government.
最聪明、最有才能的政府成员之一。
be able to
If you are able to do something, you have skills or qualities which make it possible for you to do it.
can
The older child should be able to prepare a simple meal.
这个大点儿的孩子应该能做顿简单的饭菜。
The company says they're able to keep pricing competitive.
这个公司说他们能够保持价格竞争力。
If you are able to do something, you have enough freedom, power, time, or money to do it.
You'll be able to read in peace.
你将可以安静地看书。
Have you been able to have any kind of contact?
你取得任何联系了吗?