Englishfor English speakers
is
Verb
—
A form of the verb be when talking about someone or something else.
He is late for class.
Is it hot in here?
able
Adjective
—
If someone is able to do something, he can do it.
I'm busy tomorrow, so I won't be able to see you.
—
If a person is able, he is good or skillful at what he does.
She is an able teacher.