Defective verbs

Modal verbs or modal verbs are a fairly familiar type of verb. We come across it a lot while learning and using English. So are they similar and different from regular verbs? Let's find out with EnglishTopVN through the article below

1. Concepts

Defective verbs is special type of verb that only accompanies and performs the function of supporting the main verb in a sentence and does not stand alone as a main verb in a sentence.

Common modal verbs in English include the words:

Can Could May Might Must
Ought to Should Shall Would will


Modal verbs have some differences from other regular verbs. Let's take a look at their characteristics below.

2. General structure of modal verbs

2.1. General structure

S + Modal Verbs + V(bare-infinitive)

  • (bare-infinitive: the infinitive without “to”)

For example:

  • They can speak French and English.
2.2. No variation in terms

For example:

  • He can use our phone.

2.3. Exists in Present tense and Simple Past tense

For example:

  • She can cook meals.

  • She could cook meals when she was twelve.

3. Common modal verbs

3.1. Can

  • CAN has only 2 tenses: Present and Simple Past. In other forms we use the equivalent verb "be able to". CAN can also be used as an auxiliary verb to form certain expressions.

Using For example
- CAN and COULD means "can", expressing an ability.
  • Can you swim?
  • She could ride a bicycle when she was five years old.
- In colloquial speech, CAN is used instead MAY to express a permission and negative form CANNOT is used to express a prohibition.
  • In London buses you can smoke on the upper deck, but you can’t smoke downstairs.
- CAN also describes something that could happen (possibility). In questions and exclamations CAN means 'Is it possible…?'
  • Can it be true?
- CANNOT used to describe something that is unlikely to happen (virtual impossibility)
  • He can’t have missed the way. I explained the route carefully.
- When used with verbs of perception (verbs of perception) CAN gives the same meaning as Continuous Tense.
  • Listen! I think I can hear the sound of the sea.
    (do not use I am hearing)

3.2. Could

Using

For example

- COULD is the simple past tense of CAN.

  • She could swim when she was five.

- COULD also used in conditional sentences.

  • If you tried, you could do that work.

- In informal speech, COULD considered more polite CAN.

  • Can you change a 20-dollar note for me, please?

  • Could you tell me the right time, please?

- COULD is used to express a doubt or a mild protest.

  • His story could be true, but I hardly think it is.

- COULD – WAS/WERE ABLE TO:

+ If the action expresses an ability, a knowledge, COULD used more often WAS/WERE ABLE TO.

+ If the sentence implies a success in doing the action (succeeded in doing) then WAS/WERE ABLE TO is used rather than COULD.

  • The door was locked, and I couldn’t open it.

  • I finished my work early and so was able to go to the pub with my friends.

3.3. May  - Might

Using

For example

- MAY and past form MIGHT Expresses permission or permission.

  • May I take this book? – Yes, you may.

  • She asked if she might go to the party.

- MAY/MIGHT Used to express a possibility that may or may not happen.

  • May I take this book? – Yes, you may.

  • She asked if she might go to the party.

- Used in exclamations, MAY/MIGHT express a wish.

  • May all your dreams come true!

-MAY/MIGHT used in clauses following the verbs hope and trust.

  • I trust (hope) that you may find this information useful

  • He trust (hoped) that we might find the plan to our satisfaction.

- MAY/MIGHT used instead of an adverb clauses of concession.

  • He may be poor, but he is honest. (Though he is poor…)

  • Try as he might, he could not pass the examination. (Though he tried hard…)

- MAY/MIGHT often used in adverb clauses of purpose. In this case, people often use it CAN COULD to replace MAY/MIGHT

  • She was studying so /that she might read English books.

- MIGHT (not used MAY) is sometimes used in a sentence to express a petulant reproach.

  • You might listen when I am talking to you. (Please try to listen to me)

  • You might try to be a little more helpful.
    (Please try to be a little helpful)


3.4. Must

Using

For example

- MUST means “must” expresses an order or a compulsion.

  • You must drive on the left in London.

- MUST used in logical reasoning sentences.

  • Are you going home at midnight? You must be mad!

- MUST NOT (MUSTN’T) describes a prohibition.

  • You mustn’t walk on the grass.

- When you want to express the negative form of MUST with the meaning "unnecessary" people use NEED NOT (NEEDN’T).

  • Must I do it now? – No, you needn’t. Tomorrow will be soon enough.

3.5. Shall
Using For example
- Used in Future tense structures (Simple Future) in the first person.
  • I shall do what I like.
- Expresses a promise (promise), an assertion (determination) or a threat (threat).
  • If you work hard, you shall have a holiday on Saturday. (promise)
  • He shall suffer for this; he shall pay you what he owes you. (threat)
  • These people want to buy my house, but they shan’t have it. (determination)

3.6. Should
Using For example
– Used in a sentence to advise someone on what to do, and is equivalent to ought to.
  • You should do what the teacher tells you.
– Use instead of must when you do not want to express a meaning that requires someone to do something.
  • Members who want tickets for the dance should apply before September 1st to the Secretary.

3.7. Will
Using For example
– Used in the Future tense (simple future), expressing a plan, willingness, promise or determination.
  • All right; I will pay you at the rate you ask.
  • I won’t forget little Margaret’s birthday. I will send her a present. (promise). 
– Used in proposal sentences.
  • Will you shut the door? (Will you close?)

3.8. Would
Using For example
– Used to form Future in the past or tenses in conditional sentences.
  • He said he would sent it to me, but he didn't.
  • If she were here, she would help us.
  • He would have been very happy if he had known about it.
– Describe a habit in the past. In this sense, WOULD can be used instead of used to.
  • Every day he would get up at six o’clock and light the fire.

3.9. Ought to
Using For example
– OUGHT TO also used to express an approximation, very likely to be true (strong probability).
  • If Alice left home at 9:00, she ought to be here any minute now.
– OUGHT TO Can be used in the future with words that determine future time such as tomorrow, next Tuesday...
  • Our team ought to win the match tomorrow.
– OUGHT NOT TO HAVE + past participle Expresses disagreement about an action done in the past.
  
  • You ought not to have spent all that money on such a thing.


- OUGHT TO means “should”, similar to should. In most cases OUGHT TO can be replaced with should.
For example:

  • They ought to (should) pay the money.
  • He ought to (should) be as hamed of himself.

== Bài Tập ==

 Động từ khiếm khuyết - Đề 1

 Động từ khiếm khuyết - Đề 2

 Động từ khiếm khuyết - Đề 3