smith has been suffering from akind of disease (for which the cure is possible)括号里为什么用介词for啊?

Mr.Smith has been 什么hospital什么last month Mr.Smith has been here since the factory opened为Mr.Smith has been here since the factory opened为什么用has been? Mr.Smith is not at home.He___to work.A.has gone B.has been C.had been D.had gone Mr. Smith _____from Canada. He____here last year A .went;has been B.has been;has come C.was;has beenD. has come ; is Mr Smith ___ at this school since he ___ to Zhuhai.A:has been taught; came B:has taught; has comeC:has been teaching; has come D:has been teaching; came为什么选D?has been teaching是什么时态? (Mr.Smith's passport) has been issued括号里面的是什么关系啊?不是主谓,是. Mr Smith ________ to America 10 years ago and has been there___________. If Mr Smith _______ here, he would have helped youhad beenB. wasC. wereD. has been 高中英语选择it is said that __ Smith has been appointed manager填什么冠词 为什么 Mr.Smith has been ____in his research for more than 3 hours. Mr Smith with his parents ______ China since two years ago.A .have been in B has been C has been to说明理由 mr smith has been a professor since 1994 保持原句意思：保持原句意思：mr smith has （ ）（ ）a professor for about ten years Is Mr.Smith still in Shanghai?—Yes,he ______ there for two months.A.has beenB.has goneC.has been toD.has gone to Mr.Smith as well as his wife and daught ,to their school education a have gone b has gonec have been d has been Mr Smith __________ at this school since he ________ Xiamen .A.has been teach,came B.has been teaching,came C.taught,came D.has been teaching,has come .Mr.Smith has been working in China ___________ 2000.　　A.in　　　　　　 B.for　　　　　 C.since　　　　　　 D.until Mr.Smith is the only one of these foreiners who____in china.works 还是is working还是has been working has been