一般过去时和现在完成时一. A. 用 already或 yet1) Have they taken down the old pictures _ _? No, they havent_ _.2) Most of us have finished our compositions _ .3) He said he hadnt visited the exhibition _ _.B.用 since或 for1) We have learned five lessons _ _ _ the beginning of this term.2) Mrs Liao has been in hospital _ _ _last week.3) I have stayed at my aunts _ _two weeks.C. 用have gone或 have been1) Where are the boy students? They _ to
