The following are modal verbs:

Whether modals, modal verbs, modal auxiliaries or modal auxiliary verbs, they are all the same. The modal verbs and the primary verbs (be, do and have) are called auxiliary verbs. The difference between these two groups of verbs is that we can use modal verbs as auxiliary verbs only. In other words, we cannot use modal verbs on their own in a sentence, as they are not complete by themselves. We have to use them with other verbs, which must be in the simple present tense.

There are 11 modal verbs: cancouldmaymightwillwouldshallshould, and must. Words such as had betterought to, used to, need, and dare are semi-modal verbs as they can function as modal verbs as well as main verbs. Each of the modal verbs is used with another verb to express ideas such as ability, necessity, obligation, permission, possibility, wish, etc. that are not expressed by the main verb. Each one of them can express more than one of these ideas. 

Characteristics of modal verb
The following are characteristics of modal verbs:
  • When used with singular or plural subject or noun, the modal verbs do not change their forms: (She will arrive later. / They will arrive later.)
  • Modal verbs have no –s form such as when they follow the third person singular subject. (Not: She wills talk to us later. / Not: He shoulds get some rest.)
  • Modal verbs do not have present participle form (Not: modal verb + ing).
  • Modal verbs do not have past participle form (Not: modal verb + ed). 
  • Modal verbs do not have infinitive form. They are followed by the infinitive of a simple verb without to (Not: He can to drive a tractor.) There are exceptions: ought to (You ought to be able to read the road sign from here.) and used to (We used to cross that river by ferry.)
  • Modal verbs cannot be used with another modal verb. (Not: We can must get it done today.)
  • Modal verbs cannot be used on their own in a sentence. They must be followed by other verbs. (No: The repair would one hour. / Yes: The repair would take one hour.)
  • Modal verbs can however be used on their own when the main verb is understood. (He could be sleeping. Yes, he could. / She may be angry. Yes, she may.)
  • When a modal verb is part of a verb phrase in a sentence, it comes first after the subject and (1) is followed by a main verb in the base form (Subject + modal + basic verb + ... ): She can play the flute. Or (2) is followed by an auxiliary verb (bedohave): He could be watching television at this time. 

 

Modal verbs always come before the main verb. Both the modal verbs and main verbs are in bold.

Examples:

  • This morning, my grandmother appeared more cheerful than my grandfather.
  • Smoking can causecancer.
  • The train could arriveanytime now.
  • She may getmarried next year.
  • We might reachthere before it gets dark.
  • He will giveus a lift to the circus.
  • would hateto tell her the truth.

 

Modal verb in question
Modal verbs always come before the other verbs, but to form a question, the moral verbs are placed before the subject. 

 

Examples:

  • Will everyone join with me in singing the national anthem?
  • Must you always drink coffee to keep you awake?

 

Modal verb in yes-no question
In yes-no questions, modal verbs appear before the subject. In reply to the questions, the modal verb + not can be in shortened form.

 

Examples:

  • Can you play mahjong? Yes, I can. / No, I can't.
  • Will you help me wash my car? No, I won't.
  • Would you do that for me? No, I wouldn't.
  • Should I lend him the money? No, you shouldn't.

 

Modal verb in question tag
Modal verbs are used in question tags.

 

Examples:

  • You would like some ice cream, wouldn’t you?
  • It shouldn’t be kept as a pet, should it?

 

Modal verb and contraction

Modal verbs must be placed before the word not or its contraction –n’t (couldcouldn’t) in negative sentences. The only modal verb that does not have contraction is may.  

Examples:

  • We could not read his handwriting. / We couldn't read his handwriting.
  • She should not argue with her grandmother. / She shouldn't argue with her grandmother.
  • You must not simply do what you like around here. There are rules to follow.
  • He ought not to be so rude to her. / He oughtn't to be so rude to her.
  • You may not see her. Her father doesn’t allow it. / Not: You mayn’t see her.

 

Modal verb and emphasis
When emphasis is intended, the moral verb is used in full. 

 

Examples:

  • We shall not let them do this to us.
  • Not: We shan’t let them do this to us.

 

Modal verb and wh-question
Wh-questions begin with what, when, where, who, whom, which, whose, why and how. All these wh-question words can be placed before the modal verbs to form wh-questions.

 

Examples:

  • What can you do to help us?
  • When may I have my money back?
  • Where should we start looking for the missing puppy?
  • Who could pass me the salt?
  • Whom might I ask you want to speak to?
  • Which will growl if we get too close to it?
  • Whose would you say this is?
  • Why must you be so stubborn?
  • How shall we address the Queen?

 

Modal verb and adverb
When there's an adverb in a sentence, the modal verb comes before the adverb.

 

Examples:

  • can just imagine your sister as a police officer.
  • Our team could yet win – you never know
  • He will soon be as tall as his father.
  • She would always turn her face away when she saw me.
  • You might still prove me wrong
  • shall never forget your beautiful face.
  • You should only say sorry when you mean it.