She has worked as a secretary for four years.句子中为什么要as?

She has worked as a secretary for four years.句子中为什么要as? She _____ as a nurse ____ a year A.works;since B.has worked;for C.has worked ;since D.worked;for要原因,详细 She has (work) as a nurse for three years.为什么填 worked 请说明原因, She （ ）as an animal trainer since 2003 A.has worked B.works C.will work D.worked 并告诉我原因 she ( )as an animal trainer since 2003 用worked 还是has work edworked 与has worked 的区别 She said that she ____ in that country since 1953.A.has worked B.had worked C.works D.worked ___ then,my mom has worked as a teacher. She worked(as)a teacher for many years.怎么翻译? when she worked as a graceful model in London She left school 3 years ago and has worked as a nurse ever since.和She left school 3 years ago and has been working as a nurse ever since.两种都可以的吧?翻译出来有什么不同? She left school three years ago and has worked as a nurse ________.A since then B ever since 填哪个?为什么? She said that she there the next year .A.has worked B.had worked C.was.She said that she there the next year .A.has worked B.had worked C.was working D.would working选哪个? your colleague's spoken English is quite good,Amy.No wonder,as she __in the USA for 2 years.A worked B.has worked为什么选A不选B?表示对现在造成影响 he has worked as a teacher for only two weeks .he has little e ____ the answer is A,why not use tell me why ,thanks-your english teacher's spoken english is very standard,wang ping.-it's no wonder.she ___ in the UK for a year as a visiting scholar.A worked B has worked C had worked D has been working She _______there for four years.A.works B.worked C.has worked 那答案为什么是B My aunt has worked as a secretary____2000.A.in B.since C.on D.for 谁知道,Li Hua ______ in the factory since she left school ten years ago.A.works B.worked C.has worked D.had worked