MODAL VERBS

MODAL VERBS

1. REQUESTS, OFFERS AND SUGGESTIONS

   • To ask someone to do something for us
     • MORE POLITE
       • Could
       • Would
     • LESS POLITE
       • Can
       • Will
   • To offer to do something
     • Can
     • Could
     • Shall
     • Would
   • For suggestions
     • Can
     • Could
   • The sentences use the bare infinitive

2. PERMISSION

   • To ask for permition
     • MORE POLITE
       • Could / Couldn't
       • May / May not
         • + Bare infinitive
     • LESS POLITE
       • Can / Can't-Cannot
   • To give or refuse permission
     • Can / Can't - Cannot
     • May / May not
       • + Bare infinitive
   • To permission in the present or the future
     • Be allowed to
       • EXAMPLE: He won't be allowed to go the musem today.
     • Can
       • + bare infinitive
   • For permission in the past
     • Particular occasion
       • was / were allowed to
     • General permission
       • was / were allowed to
       • Could allowed to

3. OBLIGATION AND NECESSITY

   • To say that something is neccesary
     • In the present or future
       • Must
         • + bare infinitive
       • Have got to
     • In the presente, past or future
       • HAVE
         • Had / Have / Will Have... to
       • NEED
         • Needed / Need / Will need.. to

4. LACK OF OBLIGATION AND PROHIBITION

   • LACK OF OBLIGATION: To talk about something
     • that isn't necessary in the present and future
       • Don't have / need to
       • Needn't
         • + Bare infinitive
     • That wasn't necessary in the past
       • Didn't have / need... to
       • needn't have
         • + past participle
   • PROHIBITION: To say that something isn't allowed
     • Musn't
       • + Bare infinitive

5. POSSIBILITY

   • To talk about possibility in the present or future
     • May
       • + Bare infinitive
     • Might
     • Could
       • We don't use COULD in negative
   • To talk about possibility in the past
     • May have
       • + Past participle
     • Might have
     • Coud have

6. ADVICE, RECOMENDATION AND CRITICISM

   • To give advice
     • Should
     • ought to
       • + Bare infinitive
   • To talk about what we think is right or wrong
     • Should
     • Ought to
       • + Bare infinitive
   • To express criticism of someone's actions
     • should
       • + have + past participle
     • ought to

7. DEDUCTION

   • To show that we are almost certain that something IS TRUE
     • must
   • To show that we are almost certain that something ISN'T TRUE
     • can't
       • + bare infitive
   • To talk about the past
     • must
     • can't
       • + have + past participle

8. ABILITY

   • For a general ability
     • in the past
       • Could / Couldn't
     • in the present
       • Can / Can't - Cannot
     • in the past, present or future
       • be able to
         • Was / Is / Will be able to
         • Were / Are /Will be able to
   • For a single especific ability
     • In the past
       • We can't use COULD
   • The sentences use the bare infinitive

9. STRUCTURE

   • POSITIVE
     • Subject + Modal Verb + Verb + Complement
   • NEGATIVE
     • Subject + Modal Verb + not + Verb + Complement
       • NOTE: Not all modal verbs apply the sentences in positive, negative and question at the same time.
   • QUESTION
     • Modal Verb + Subject + Verb + Complement