Auxiliary verbs

Auxiliary verbs are used with main verbs to construct the verb phrase. They fall into two groups:

• Primary auxiliaries
• Modal auxiliaries

Primary auxiliaries
The primary auxiliaries are: be, have, and do. They are used in clauses such as:

I am eating bread.
They have eaten bread.
You do eat bread.

Primary auxiliaries can also work as main verbs. For example:

I am happy to see these names included.
I have a new life now and new friends.
We do things that are controversial.

Modal auxiliaries

These are used in clauses such as:

I shall eat bread.
I might eat bread.
I could eat bread.

Modal auxiliaries cannot work as main verbs and normally appear with a main verb. The full list is:

There is a big difference between the meanings of the two sets of auxiliaries. The sentence that follows illustrates this:

It must work dependably.

If you change this to It does work dependably, you are saying something very different. We can use the contrast between the two types of auxiliary to make a point, as in this example:

Britain's labour market may be working better but it is still not working well.

To sum up: modal auxiliaries create a range of possible situations from may through will to must. The primary auxiliaries deal in actual situations.

©John Seely 2008