Modal Verbs 2

When are modal verbs used?

What special conditions do modal verbs indicate? Here’s a list, along with examples:

Likelihood

Some things seem likely to be true but can’t be stated as definite facts. In these cases, you can use the modal verbs should and must to show probability without certainty.

Example: Her parents must be so proud.

Example: My baby brother should be asleep by now.

Possibility

In a situation when something is possible but not certain, use the modal verb could, may, or might.

Example: Judging by the clouds, it might rain today.

Example: She may become the youngest pro soccer player ever.

Ability

The modal verb can expresses whether the subject of a sentence is able to do something. Likewise, the negative form, cannot or can’t, shows that the subject is unable to do something.

Example: She can speak three languages but none of them well.

Example: You can lead a horse to water, but you can’t make it drink.

Permission

If you want to ask permission to do something, start your question with can, may, or could. Traditionally, may is considered more formal and polite usage for permission; if you ask “Can I go to the bathroom?” it could be misinterpreted as “Do I have the ability to go to the bathroom?” However, in modern informal usage, may and can are both perfectly acceptable options for describing possibility or permission.

Example: Students, you may leave early today.

Example: Could I play too?

Request

Similarly, if you want to ask someone else to do something, start your question with will, would, can, or could.

Example: Would you get that box off the top shelf?

Example: Will you turn that music down?

Suggestion/advice

What if you want to recommend a course of action but not command it? If you’re giving suggestions or advice without ordering someone around, you can use the modal verb should.

Example: You should try the lasagna.

Example: That guy should wear less cologne.

Command

On the other hand, if you want to command someone, use the modal verbs must, have, or need. With the latter two, the main verb does not drop the word to from its infinitive form.

Example: You must wash your hands before cooking.

Example: You need to be here before 8:00.

Obligation or necessity

Modal verbs can express a necessary action, such as an obligation, duty, or requirement. Likewise, the negative forms express that an action is not necessary. Use the same modal verbs as with commands: must, have, and need.

Example: We have to wait for our boss to arrive before we open.

Example: You don’t need to come if you don’t want to.

Habit

To show an ongoing or habitual action—something the subject does regularly—you can use the modal verb would for the past tense and will for the present and future. The phrase used to is also acceptable when you’re talking about a habit in the past.

Example: When I lived alone, I would fall asleep with music.

Example: I will arrive early to every meeting and leave late.