i used the excellent presentation from Anabel Ponce but made a few corrections and changes.

1. MODALMODAL VERBSVERBS

2. Can/ Be able to / Can’tCan/ Be able to / Can’t
 CANCAN
 Different uses:Different uses:
 Abilities or capacities (to know or toAbilities or capacities (to know or to
be able to).be able to).
 Mary can swim very fast.Mary can swim very fast.
 Request, ask or give permissionRequest, ask or give permission
 Can you call me tonight?Can you call me tonight?
 PossibilityPossibility
 I can meet you later.I can meet you later.
 It can also be used for suggestions.It can also be used for suggestions.
 You can eat ravioli if you like pasta.You can eat ravioli if you like pasta.

3.  Be able toBe able to
 It expresses abilities likeIt expresses abilities like cancan and it is usedand it is used
in all the verbal tenses wherein all the verbal tenses where cancan is notis not
used.used.
 I was able to finish my homework on timeI was able to finish my homework on time
 Can’tCan’t
 Different uses:Different uses:
 Impossibility in the presentImpossibility in the present
 Mary can’t swim very fastMary can’t swim very fast
 Lack of ability (not to know) or capacity (not toLack of ability (not to know) or capacity (not to
be able to): I can’t eat a whole cake by myselfbe able to): I can’t eat a whole cake by myself
 ProhibitionProhibition
 You can’t drive without a licenceYou can’t drive without a licence
 DisbeliefDisbelief
 That can’t be the price! – it’s much too cheap.That can’t be the price! – it’s much too cheap.

4. CouldCould
 It is the past ofIt is the past of cancan and it is used toand it is used to
express:express:
 Ability or capacity in the pastAbility or capacity in the past
 She could run fast when she was a childShe could run fast when she was a child
 Polite requestPolite request
 Could you help me with these suitcases?Could you help me with these suitcases?
 Polite suggestionPolite suggestion
 You could exercise and eat healthier food!You could exercise and eat healthier food!
 Possibility –less probable than withPossibility –less probable than with can-can-
 Mark could join us at the cinema.Mark could join us at the cinema.

5. May/ mightMay/ might
 Both of them express possibility,Both of them express possibility,
butbut mightmight is more remote.is more remote.
 It may/ might rain tomorrowIt may/ might rain tomorrow
 In questions, may is the politeIn questions, may is the polite
way of asking for things.way of asking for things.
 May I have a coffee, please?May I have a coffee, please?

6. WouldWould
 In questions, it is a formal wayIn questions, it is a formal way
of asking for things.of asking for things.
 Would you open the window,Would you open the window,
please?please?
 With the verb “like” is used toWith the verb “like” is used to
make offers and invitations.make offers and invitations.
 Would you like something toWould you like something to
drink?drink?

7. Must / Have toMust / Have to
 Both express obligation, butBoth express obligation, but mustmust isis
only used in the present andonly used in the present and have tohave to
in the other tenses. People inin the other tenses. People in
authority useauthority use mustmust, while, while have tohave to isis
used by everybody.used by everybody.
 You must bring your books to classYou must bring your books to class (teacher)(teacher)
 I have to buy the tickets today.I have to buy the tickets today.
 Must is also used to express a logicalMust is also used to express a logical
deduction about present facts.deduction about present facts.
 She’s got a great job. She must be veryShe’s got a great job. She must be very
happy.happy.

8. Need to / Needn’tNeed to / Needn’t
 Need toNeed to is not a modal, but it is usedis not a modal, but it is used
in affirmative sentences, likein affirmative sentences, like have tohave to,,
to express obligation and necessity.to express obligation and necessity.
 I need to cook dinner tonight.I need to cook dinner tonight.
 Needn’t, on the contrary, is a modalNeedn’t, on the contrary, is a modal
and indicates lack of obligation andand indicates lack of obligation and
necessity, likenecessity, like don’t have todon’t have to
 You needn’t bring anything to the party.You needn’t bring anything to the party.

9. Mustn’t / Don’t have toMustn’t / Don’t have to
 Mustn’tMustn’t shows prohibition.shows prohibition.
 You mustn’t smoke hereYou mustn’t smoke here
 Don’t have toDon’t have to meansmeans not havenot have
toto, i.e. lack of obligation and, i.e. lack of obligation and
necessity, likenecessity, like needn’tneedn’t
 I don’t have to get up earlyI don’t have to get up early
tomorrowtomorrow

10. Should /Ought toShould /Ought to
 Both of them express advice orBoth of them express advice or
opinion, butopinion, but shouldshould is used moreis used more
frequently, sincefrequently, since ought toought to isis
quite strange in negative andquite strange in negative and
interrogative.interrogative.
 You should improve yourYou should improve your
pronunciationpronunciation

11. ShallShall
 It is used in the interrogative toIt is used in the interrogative to
offer oneself to do somethingoffer oneself to do something
and to make a suggestion butand to make a suggestion but
usually only in the 1st personusually only in the 1st person
singular or plural.singular or plural.
 Shall I help you with yourShall I help you with your
luggage?luggage?
 Shall we eat now?Shall we eat now?

13. MODAL PERFECTSMODAL PERFECTS
 Must have + past participle (V3)Must have + past participle (V3)
 It expresses a logical conclusionIt expresses a logical conclusion
about a past fact.about a past fact.
 Rob has arrived late. HeRob has arrived late. He must havemust have
beenbeen in a traffic jam.in a traffic jam.
 May/might have + past participleMay/might have + past participle
 We use it to make a suppositionWe use it to make a supposition
about something in the past.about something in the past.
 SheShe may/might have takenmay/might have taken the wrongthe wrong
bus.bus.

14.  Could have + past participleCould have + past participle
 Ability to do something in the pastAbility to do something in the past
which in the end was not donewhich in the end was not done
 YouYou could have askedcould have asked the doctorthe doctor
before taking the medicine.before taking the medicine.
 Couldn’t have + past participleCouldn’t have + past participle
 Certainty that something did notCertainty that something did not
happenhappen
 HeHe couldn’t have gonecouldn’t have gone to the concertto the concert
because he was doing the test.because he was doing the test.

15.  Should/ought to + past participleShould/ought to + past participle
 Criticism or regret after an eventCriticism or regret after an event
 YouYou should/ought to have warnedshould/ought to have warned meme
earlierearlier
 Shouldn’t have + past participleShouldn’t have + past participle
 Criticism or regret after an event,Criticism or regret after an event,
showing that it shouldn’t have happenedshowing that it shouldn’t have happened
 HeHe shouldn’t have forgottenshouldn’t have forgotten about herabout her
birthdaybirthday

16.  Would have + past participleWould have + past participle
 Desire to do something in the pastDesire to do something in the past
which in fact could not be done.which in fact could not be done.
 II would have gonewould have gone to the party, but Ito the party, but I
was too busy.was too busy.
 Needn’t have + past participleNeedn’t have + past participle
 An unnecessary past actionAn unnecessary past action
 YouYou needn’t have broughtneedn’t have brought anything toanything to
my party.my party.

17. Should /Had betterShould /Had better
 Should/had betterShould/had better
 Had better is used in a moreHad better is used in a more
colloquial way of expressing whatcolloquial way of expressing what
someone has to do, to give advicesomeone has to do, to give advice
or opinions.or opinions.
 You’d better goYou’d better go to the doctor.to the doctor.
 It also it is used to express aIt also it is used to express a
warningwarning
 You’d better tidyYou’d better tidy your room now!your room now!