could

Universal Words 1 used as the past tense of 'can': She said that she couldn't come. * I couldn't hear what they were saying. * Sorry, I couldn't get any more. -< CAN 2 used to ask if you can do sth: Could I use your phone, please? * Could we stop by next week? 3 used to politely ask sb to do sth for you: Could you babysit for us on Friday? 4 used to show that sth is or might be possible: I could do it now, if you like. * Don't worry-they could have just forgotten to call. * You couldn't have left it on the bus, could you? * 'Have some more cake.' 'Oh, I couldn't, thank you (= I'm too full). 5 used to suggest sth: We could write a letter to the director. * You could always try his home number. 6 used to show that you are annoyed that sb did not do sth: They could have let me know they were going to be late! 7 (informal) used to emphasize how strongly you want to express your feelings: I'm so fed up I could scream! -> MODAL IDIOMS could do with sth (spoken) used to say that you need or would like to have sth: I could do with a drink! * Her hair could have done with a wash.