第6题,为啥不选b 选had been on

第6题,为啥不选b 选had been on 为啥不选B? All the letters ___,John took them to the post office.A.had been writing B.having been written C.wrote D.had written选什么为啥 选择题第6题求解释为啥选B 9题b为啥不选 I had to meet my mother at the railway station as she ( ) before.I had to meet my mother at the railway station as she ( ) before.A had never been hereB had never come here为什么答案不能选B,我觉得A和B都可以啊,为啥不能用come? 姐姐、问你一道英语选择题哈~-What place is it -Have not you found out we _______back where we ____?A、were;have been B、are;were C、were;had been D、are;had been 选什么?为啥? 英语单选 第8题 为啥不选a? 'Where were you?' His wife wanted to know where_________A he was B wasC was hed he had been请告诉我为什么选第D ,不选A, Not only his parent but also his uncle () there beforeA has been B had been 为什么不选B do you know where ——?A.she had beenB.had she been C.had she gone D.she had gone 为什么选A不选B呢? 第第二题,为啥选B,英语题 ＿for their help ,we would not have overcome the difficultiesa were not b had it not been c had not it been d had it been not 为什么不选c ---for their help ,we would not have overcome yhe diffculties.a were not b had it not been c had not it been d had it been not 为什么不选c请详解 All the flights____because of the snowstorm,we had to take the train instead.A.were canceled B.had been canceled C.having canceled D.having been canceledD独立主格为啥不是B 不用独立结构不行吗? 为啥选B?不选D after searching for half an hour ,she realized that her glasses ( )on the table all the time.A.had been lying B.have been lying C.had been lain D.were lain选A,问什么不选B? I could have arrived on time for the conference,but our flight _ because of the fog.A.was delayed B.had been delayed 为啥不选B?Mr,s Liu gave us a speech yesterday,in which she shared with us _ it took to be successful in life .A.what B.when C.whe