Understanding single-word modals and phrasal modals

Modal verbs are helping/auxiliary verbs that express ideas like ability, permission, possibility, and necessity.

One of the most important things to remember is that modal verbs are always combined with other verbs to show complete meanings, but combining correctly is often a challenge for English learners. This is because we have single-word modals (can, could, may, might, must, shall, should, will, would) and phrasal modals (be able to, be going to, be supposed to, had better, have to, have got to, ought to, used to).

All of these modals are followed by the simple form of the verb, otherwise known as the main verb or the root verb. This is the infinitive without “to”.

For example, let's look at the single-word modal for ability, "can":
- Marco "can tap dance" well. - correct
- Marco "can to tap dance" well. - incorrect

A phrasal modal that also shows ability is “be able to”. Notice that “to” is part of the phrase so we still add only the simple verb form, not the infinitive. Example,
- Francesca “is able to” speak English, Italian, and French.
- Francesca "can" speak English, Italian, and French.
Both are correct and communicate the same thing.

Remember the simple verb form when using modals and your sentences will be spectacular.