Modal Means of Expressing Ability, Permission /Prohibition

Modal means of expressing ability, permission /prohibition present Can/can’t, cannot Am,is,are able to May/may not past Could/couldn’t Was/were able to Might (only in reported speech) “Was/were allowed to” is used instead Physical or mental  Can  Having the power, skill or means ability General: I can read fast(I know how to). to do something: or in a particular case: He is able to lift a horse I can help you now.  Ability to perform an action on  Could a particular occasion (in the General: I could ride a bike at the age of 5. past):  couldn’t I could swim well and one day I was General: I couldn’t read fast in the first grade. able to swim across the Volga. or in a particular case:  When we need to use forms can I couldn’t fall asleep last night lacks:  With verbs of physical perception see, hear,etc. I haven’t been able to sleep for the past couple of nights (asking for) Can/could I take the plate? May I look at your notes?I wonder if I might ask you permission You can/could leave your car at the car park. something?(might is more tentative) (could is a more polite form) prohibition You can’t smoke here May I…?- No, you may not. They were not allowed to sit down to eat their lunch.

Modal means of expressing necessity, obligation/prohibition, advice present Must/mustn’t Have/has to Should/ought to (To be to) Need/needn’t don’t/doesn’t have to Shouldn’t/oughtn’t to Am/is/are to do Don’t/doesn’t need to (=had better do smth) past - Had to/didn’t have to - Was/were to do Needed/didn’t need to Obligation Strong obligation (imposed by Objective obligation, imposed The right thing to do, mild Obligation arising out of Necessity: rules, laws, moral duty) from outside obligation or advice an arrangement or plan: I need to see the All visitors must leave their One has to obey the rules. You ought to vote in the We are to complete this doctor. coats in the cloak room. He had to be content with a coming election. work by tomorrow. He needed to change  Personal obligation, resolution small salary. (Ought to has more of a moral If you are to be his clothes. successful you must…= if I mustn’t do it again flavour than should) you wish to be successful Prohibition You mustn’t smoke You shouldn’t write in pencil. Strict prohibition. here(=can’t)Past: We weren’t (mild prohibition) You are not to do that! allowed to smoke inside. You oughtn’t to watch scary movies (it’s not prudent) Absence/lack of You don’t have to wait for me. You needn't (don’t obligation or I’ll stay in the office till late at need to) go to the necessity night. meeting. Asking for Must one always obey the Do I have to collect all the Should I follow you? What am I (supposed) to Do I need to /Need I instructions/advice authorities? documents till tomorrow? Ought I to wear a coat? do? attend this class?