Modal verbs1What are modal verbs?I cant swim.She should study more.You must finish your homework.

Modal verbs express:PERMISSIONABILITYPROHIBITONOBLIGATION2Rules I can (to) swim.She cans swim.Can you swim? I cant swim.To can, canning, canned Must:She must do her homework.She had to do her homework yesterday.She will have to do her homework next week.Can:I can swim.I could swim when I was three.I will be able to swim after I finish my swimming lessons.3CAN/CANTAbilityI can run fast but my grandfather cant.PermissionCan I open the window?

PASTI could run fast when I was younger.4SHOULD/SHOULDNTGiving advice

She should study more.

He shouldnt play computer games all the time.5MUST/MUSTNTObligationI must study more. (I think so.)I have to study more. (my parents and teachers think so)

I dont have to study anymore. (The school has finished.)

ProhibitionChildren mustnt drink alcohol.6Modal verbUsageExamplecan/cantabilityI can do several thingsat the same time.permissionYou can go now.could/couldntpast form of "can"She said she could payfor us as well.be able tofuture form of "can"I will be able to solve this problem.mustobligation you think you have to do itYou must do my homework.must not/mustn'tprohibitionYou mustn't smoke in here.have toobligation somebody else says you have to do itI have to come to school on time.dont have tono obligationI dont have to finish my homework now.had to/didnt have topast form of "must" - OBLIGATION I had to finish my homework before dinner.should/shouldntadvice-What should I do?-You should stopthinking about it.