He worked in a foreign company at one time,___he went to Britain for further study.为什么用after which 不用after that

He said he ( ) in that factroy since 1949.A.has worked B.had worked C.worked D.was working After g( ),he worked as a clerk in a company He worked in a big history m____ last year. he worked in a lawyer office.句中有一处错误请指出. He worked in an office. =Mark ____ in China for 10 years and now he teaches Chinese in Britain.A.has worked B.worked Mark ____ in China for 10 years and now he teaches Chinese in Britain.A.has worked B.worked Mark _________ in China for 10 years and now he teaches Chinese in Britain.A.has worked B.worked C.had worked D.is working he worked a____ for a month.he isn't in china now Afer he left universit,he worked as an engineer in a big company. though he worked hard ,he still had a little difficult e himself in english.首字母填空 In the past three years ,he ____ very hard at maths. A.works B.worked C.has worked Dis workin Jim ___ in Zhuzhou since he finished his college.A.works B.is working C.has worked D.is worked His father is e__ in cooking because he worked in a five-star restaurant. Mark_in China for 10 years and now he teaches Chinese in Britain 请说明理由 回答其他答案忽略A、has worked B、worked C、had worked He works in China,but he___in Africa for 8 years.A.work B.has worked C.had worked D.has been workingA选项写错了，应该是worked. ___ he would have succeeded in the examinations.A If he has worked hard B If he works hard C If he worked hard D Had he worked hard 选什么?为什么? He works in a factory now, but he _____on a farm for 20 years. A.worked B.had worked为什么答案选了A 而不选B