Able is used especially in the structure be able + infinitive. This often has the same meaning as can. The negative form is unable.
Considering the use of ABLE in the sentences bellow, mark T for the true sentences and F for the false ones:
( ) Some people are able to walk on their hands.
( ) I am unable to understand what she wants.
( ) He is able to do so.
The correct order of the answers for the sentences above, top down, is:
