Modal Verbs. Modal verbs are used for to express obligation, advice, permission, probability, or capability.

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1 Modal Verbs Modal verbs are used for to express obligation, advice, permission, probability, or capability. Obligation Advice Permission Probability Capability + -? + have to +? - have got to + -? need to +? should + -? ought to + -? can + -? - + -? be able to + -? may? + -? might + -? + statement - negative? question Be careful to avoid the common confusion between and have to: = il faut have to = il faut n t = il ne faut pas don t have to = vous n êtes pas obligé Verbs + to + infinitive be able ought have (when = ) verbs + infinitive (without to) can could may might should

2 The Tenses of the Modal Verbs Use of modal verb Present Future Past N/A obligation have / has to will have to had to need / needs to will need to needed to should should should have capability can N/A could am / are/ is able to will be able to was / were to have may may may have possibility could could could have might might might have can t can t can t have to + infinitive N/A: Non Applicable have + past participle can Modal Verbs in Detail Pouvoir: My boss says I can leave work early tonight. Savoir faire: I can speak English. Present can can t / cannot Past could couldn t Future will be able to won t be able to Could and may are also used in questions in the present tense for politeness: Can/could/may I help you? May is also used to express possibility: Inflation may increase this month = It is possible that inflation increases. Might is used to express a very small possibility: I might win the lottery one day. should Devoir (advice): I should learn German for my job = It is a good idea. Present should shouldn t Past should have + past participle shouldn t have Future N/A N/A Ought to means the same as should: I ought to learn German for my job.

3 Devoir (obligation): You speak English during your English training. Present n t Past N/A N/A Future N/A N/A have to Have to =. Children have to go to school = they go to school Don t have to Children don t have to go to university. = they can choose (change in meaning) Present have to don t have to Past had to didn t have to Future will have to won t have to need to Need to = avoir besoin de I need to learn English for my job = J ai besoin d apprendre l anglais pour mon travail. Needn t / don t need to = don t have to I don t need to clean my car = I don t have to clean my car = Je n ai pas besoin de nettoyer ma voiture. Present need to needn t / don t need to Past needed to didn t need to Future will need to won t need to

4 Obligation, Capability, Probability Modal verbs express many different concepts which fall into three basic categories: obligation (or lack of it), capability (or incapability) and probability. 1. OBLIGATION (including permission and advice) have to have got to need to should ought to needn t don t have to shouldn t oughtn t to n t strong obligation mild obligation / advice no obligation / choice given strong advice forbidden obligation: You speak English during your English training. to insist on doing something:you meet them; they re really nice. Present n t Past N/A N/A Future n t have to The same meaning as except that the decision is imposed by somebody other than the speaker. Children have to go to school = the Government decides You have to start work before 9.00a.m(the company decides) Don t have to n t. Mustn t = il ne faut pas : You n t smoke in the labs. Don t have to = pas d obligation : You don t have to work until 8.00 p.m. at night. Therefore, even if you want to imply, in a negative phrase, that somebody else has imposed the decision, you can only use n t. The company rules say that you n t smoke in your office. Not: The company rules say that you don t have to smoke in your office. (change in meaning) Present have to don t have to Past had to didn t have to Future will have to won t have to

5 have got to Can replace have to or, especially in spoken English: I ve got to go to the doctor s tonight. The negative means the same as don t have to but is rarely used. (change in meaning) Present have got to haven t got to Past N/A N/A Future have got to haven t got to need to Expresses obligation when used in a question: Do I need to get permission to go home early? Expresses no obligation when used in a negative sentence: You don t need a visa to go to Spain. (change in meaning) Present Do I need to? I don t need to Past Did I need to? I didn t need to Future Will I need to? I won t need to should It is a good idea: I should learn all the irregular verbs. Advice: You should fix that machine; its dangerous. To indicate morality: He should pay you more money to do that job. To indicate regret: I shouldn t have refused the offer. Present should shouldn t Past should have + past participle shouldn t have + past participle Future should shouldn t ought to Means the same as should: I ought to learn all the irregular verbs. The negative form is rarely used. Present ought to oughtn t to Past ought to have + past participle oughtn t to have + past participle Future ought to ought to

6 can It is allowed: My boss says I can leave work early tonight. Giving permission: You can stop working for today. Present can can t / cannot Past could + infinitive couldn t + infinitive Future will be able to won t be able to may In questions to ask for permission: May I leave work early today? Note that can and could are also used in questions: Can/could I help you? 2. CAPABILITY Can Express ability: I can speak three languages. Present can can t / cannot Past could + infinitive couldn t + infinitive Future will be able to won t be able to Be able to Expresses ability - the same signification as can - in the present: I am able to speak three languages. Expresses ability on one particular occasion when used in the past tense. I was able to beat James at tennis yesterday. Present am / are / is able to am not / aren t / isn t able to Past was/ were able to wasn t / weren t able to Future will be able to won t be able to

7 3. PROBABILITY may could might can t 95% certain 5 % certain almost certain: The man with her be the new recruit. He got very good results; he have worked very hard. When considering probability, the negative form of is not n t but can t : He can t be that old. He failed his exams; he can t have worked very hard. statements Present can t Past have + past participle can t have + past participle Future N/A N/A can t To make almost certain (negative) deductions about the past: She can t have gotten lost. We also use couldn t have: She couldn t have gotten lost. Present N/A N/A Past N/A can t have + past participle couldn t have + past participle Future N/A N/A could It is a possible explanation: That could be the reason why it doesn t work. Expresses past probability: She couldn t have gotten lost. Expresses future possibility: There could be a storm later. You are considering doing something: I suppose we could send the parts next week. In negative questions for suggestions: Couldn t we employ more staff? (why don t we?) Present could + infinitive couldn t + infinitive Past could have + past participle couldn t have + past participle Future could + infinitive couldn t + infinitive

8 May Express future possibility: Inflation may increase this month. Express past possibility: She may have left the company. Present may may not Past may have + past participle may not have + past participle Future may may not Might Express a small future possibility: I might win the lottery one day. To make a suggestion: We might compare notes = we can, if you like Present might might not Past might have might not have Future might might not