Mr.Smith has been ____in his research for more than 3 hours.

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'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 Mr.Smith has been ____in his research for more than 3 hours. 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 Mr. Smith _____from Canada. He____here last year A .went;has been B.has been;has come C.was;has beenD. has come ; is 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 ___ 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 with his parents ______ China since two years ago.A .have been in B has been C has been to说明理由 Mr.Wang has never been to England,__?A.hasn’t he B.has Mr.Wang C.hasn’t Mr.Wang D.has he Mr Smith has a _______ daughter Mr.Smith has a (v)big room. 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 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