A verb is often called a 'doing word' or an 'action word'.

Jacob raced down the hill on his bike.

Sometimes a verb is made up of more than one word:

Jacob was riding his bike this morning.

We don't just use verbs to describe action, though. A verb can also give us information about someone or something.

Jacob is nine years old. He loves football.

One important thing to remember is that every sentence needs a verb.