English Modal Verbs

Modal verbs are common auxiliary verbs in Germanic languages including English that indicate modality. Modality is the expression of possibility, necessity, and contingency.

The nine modals verbs in English are:

• can
• could
• may
• might
• must
• shall
• should
• will
• would

Modal verbs always appear in the first position at the beginning of the verb phrase in English. Unlike other verbs, modal verbs do not show tense or number. The seven possible verb phrase combinations that contain modal verbs in English are:

• modal verb + base form = will eat
• modal verb + be + present participle = will be eating
• modal verb + have + past participle = will have eaten
• modal verb + be + past participle = will be eaten
• modal verb + have + been + present participle = will have been eating
• modal verb + have + been + past participle = will have been eaten
• modal verb + have + been + being + past participle = will have been being eaten

Although most varieties of English only allow for the use of one modal verb per verb phrase, some English dialects such as Southern American English allow for double modals. For example, the double modal might could as in He might could build a new machine shed expresses both possibility and ability. However, prescriptive grammars proscribe against the use of double modals.

Modal verbs are difficult to define in any language because of the wide range of pragmatic uses of modal verbs by native speakers. Some of the more common definitions (in no particular order) of the modal verbs in English are:

• can – ability, permission, possibility, request
• could – ability, permission, possibility, request, suggestion
• may – permission, probability, request
• might – possibility, probability, suggestion
• must – deduction, necessity, obligation, prohibition
• shall – decision, future, offer, question, suggestion
• should – advice, necessity, prediction, recommendation
• will – decision, future, intention, offer, prediction, promise, suggestion
• would – conditional, habit, invitation, permission, preference, request, question, suggestion

The following sentences are examples of usage of modal verbs in English. For example, the following four sentences all ask for permission but with different degrees and types of modality:

• Can I go to the bathroom? (asking for permission)
• May I go to the bathroom? (more politely asking for permission)
• Could I go to the bathroom? (asking for permission with less certainty)
• Might I go to the bathroom? (asking for permission with uncertainty)

The following sentences also demonstrate the subtle meanings in regards to modal verbs of suggestion:

• You could listen to me. (suggestion)
• You might listen to me. (uncertain suggestion)
• You should listen to me. (strong suggestion)
• You must listen to me. (stronger suggestion)
• You will listen to me. (strongest suggestion)

The meanings of modal verbs are very pragmatic and must be learned through use.

Identify the modal verb and modality (definition) in the following sentences.

Sentences

1. You could ride your bike across the country, but I advise against it.
2. Since all dogs are mammals, this golden retriever must be a mammal.
3. You might consider finishing your degree.
4. I will finish my essay tonight even if I have to forgo sleep.
5. The puppy can sit on command.
6. I would eat cereal every day as a child.
7. You may encounter some difficult patrons on occasion.
8. The train should arrive in a few minutes.
9. The situation would not be so bad if we all remained calm.
10. I will have earned my graduate degree next spring.

Possible Answers

1. could – possibility
2. must – deduction
3. might – suggestion
4. will – intention
5. can – ability
6. would – habit
7. may – probability
8. should – prediction
9. would – conditional
10. will – future

For a printable reference sheet on English modal verbs, please download the supplement to this article English Modal Verbs Reference Sheet.

For information on other verb forms in English, please read the article The English Verb System for ESL Students.

For more information on verbs, please see:

• The Functions of Verbs and Verb Phrases in English
• Parts of Speech: Verbs
• Action Verbs and Verbs of Being Lesson