Able means you can do something because you have the skill or strength. It shows the power to do an action.
She is able to swim well.
He is able to speak English.
Able can show that something might happen or can be done in the future. It means it is possible.
It is able to rain tomorrow.
The machine is able to break down.
Able can mean that a person is healthy or strong enough to do something, often used in medical or formal language.
The patient is able to work again.
After recovery, she is able to walk.