On this page you'll find out what an auxiliary verb is and how to use it.

Auxiliary verbs could be called helping verbs: they don't mean anything when they are alone, but when in a sentence, they help complete the form and meaning of main verbs. The most common auxiliary verbs are:

There are two verbs in each of these sentences:


auxiliary verb

main verb

rest of the sentence




my keys.




this band.

The hotel



ten years ago.

In the above examples, the verbs in bold are auxiliary verbs.

Now that you know what an auxiliary verb is, let's see how they can be used in greater detail.

Short answer

Use an auxiliary verb when you want to avoid repeating some part of your sentence (because it can be deduced from the context):

Use "do", "does" or "did" for the present and past simple:

Polite interest

Apart from that, phases such as "have you?", "isn't she?" or "do they?" and so on, can be used to show polite interest in what somebody has said:

Sometimes we use these "short questions" to show surprise:

We use auxiliary verbs with "so" and "neither":

Note the word order after "so" and "neither" (verb before subject):

You can use "nor" instead of "neither":

You can also use "not... either".

"I think so" / "I hope so"

After certain verbs you can use "so" if you don't want to repeat something: