I _____n’t see, now I _____.I _____n’t listen, now I _____.He _____ seem happy, but he _____ be sad.You _____ be kind. You _____ do your best.Can and could. Will and would.May and might, ought to and should.You don’t _____ walk, no you _____n’t.I’m _____ drive, yes I can.We have to, we _____ obey the traffic lights.We can go on green, but we mustn’t on red.Don’t have to and needn’t.Able to and can.Have to and must.Mustn’t and can’t.Modal verbs.