16.They collected some valuable stamps___ they stayed in ShanghaiA.while B.as C.since D.during 麻烦帮看一下,B项为什么不正确,帮分析一下,17.I didn't manage to do it______ you had explained howA.until B.unless C.when D.before

1.Mary has collected many chinese st_____since she came here.2.They were so ex______at the good news that they jumped up.3.it is not al____to speak loudly in public,so please keep down your voice. They have collected stamps since 1986.改为被动语态 They collected eggs (on the farm).(对划线部分提问) I ＿ over 2500 kinds of stamps so far.A.collected B.have collecting C.have collected D.have beenD.have been collected ----How many stampe have you collected so far?----__ ___ ___ ____(300多张) his animals__ he collected.A so that B and that C as to D that 用适当的形式：Books,plastic,glass and so on can be collected for ___(recycle) They collected some wood to ----- (点火)for cooking.根据所给中文填空 and so they They taught me so they so tall are they are so If they say so So They Say 歌词 so what'd they They believed,and〔〕did we,→→that these modern paintings collected in the Shanghai Art Gallery were as valuable as those in the Museum.选项是:A.that B.which C.neither D.so请告诉我选A的原因. I ( )over 2500 kinds of stamps so far A.have collecting B.have collected 选哪个?为什么?翻译. He has collected many kinds of them in his bedroom ,such as bears,penguins and so on.