modal verbs
What are the differences and similarities between auxiliary and modal verbs?
Auxiliary verb
Modal verb
Modals are defective. What does this mean?
They are defective because they don’t have all the typical forms of a conventional verb. English modal verbs (can, could, may, might, must, ought, should) are defective in that they lack distinctive third-person singular, gerund and infinitive.
As a result of modals lacking tenses, those tenses are conveyed by means of other verbs and expressions. For example, what’s the future tense form of the sentences below?PRESENT:
- He must do household chores every day.
- Jane can speak Dutch.
Modal verbs can be classified according to the ideas they express. They can be a little tricky because their meanings sometimes overlap. E.g.: He couldn't park there. This sentence has two possible meanings.
Classification of modal verbs
Past form of modal verbs
Most modal verbs form their past forms in the following way: MODAL+HAVE+PAST PARTICIPLE E.g.: You SHOULDN'T HAVE BOUGHT such a pricey outfit. However, depending on the idea they express, modal verbs might show different past tense forms .E.g.:
- I must study hard for my exams.
- It must be difficult to become an astronaut.
past form of need to
NEED TO can have two different negative forms, as a modal or as a main verb with no difference in meaning. E.g.:
- I don't need to go tomorrow. (=main verb)
- I needn't go tomorrow.(=modal verb)
However, this difference in the past tense entails a shift in meaning. Can you tell the difference between the two sentences below?
- I didn’t need to buy a train ticket.
- I needn’t have bought a train ticket.
Let's practise!
Let's practise!
THANK YOU!
The verbs preceded by an asterisk are not true modal verbs. However, they are included here because they are normally used when the modal verb is not possible or because they express a similar meaning. E.g.: As a child he HAD TO (=past form of MUST) work in the fields. You HAD BETTER NOT (=SHOULD NOT)trust him. In this job you are supposedTO BE ABLE (=CAN has no infinitive)to type.
modal verbs
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Transcript
modal verbs
What are the differences and similarities between auxiliary and modal verbs?
Auxiliary verb
Modal verb
Modals are defective. What does this mean?
They are defective because they don’t have all the typical forms of a conventional verb. English modal verbs (can, could, may, might, must, ought, should) are defective in that they lack distinctive third-person singular, gerund and infinitive.
As a result of modals lacking tenses, those tenses are conveyed by means of other verbs and expressions. For example, what’s the future tense form of the sentences below?PRESENT:
Modal verbs can be classified according to the ideas they express. They can be a little tricky because their meanings sometimes overlap. E.g.: He couldn't park there. This sentence has two possible meanings.
Classification of modal verbs
Past form of modal verbs
Most modal verbs form their past forms in the following way: MODAL+HAVE+PAST PARTICIPLE E.g.: You SHOULDN'T HAVE BOUGHT such a pricey outfit. However, depending on the idea they express, modal verbs might show different past tense forms .E.g.:
past form of need to
NEED TO can have two different negative forms, as a modal or as a main verb with no difference in meaning. E.g.:
- I don't need to go tomorrow. (=main verb)
- I needn't go tomorrow.(=modal verb)
However, this difference in the past tense entails a shift in meaning. Can you tell the difference between the two sentences below?Let's practise!
Let's practise!
THANK YOU!
The verbs preceded by an asterisk are not true modal verbs. However, they are included here because they are normally used when the modal verb is not possible or because they express a similar meaning. E.g.: As a child he HAD TO (=past form of MUST) work in the fields. You HAD BETTER NOT (=SHOULD NOT)trust him. In this job you are supposedTO BE ABLE (=CAN has no infinitive)to type.