抗原表面与抗体结合是什么

He said he had worked in that factory since 1949.这句是过去完成时的句子,那他现在还在工厂工作吗? "the children are so excited that they can’t w...to open the box." My mother was -------(clean) up the kitchen this morning.why?/ let\'s have a He lent me a bike,改被动语态改成A bike____by him 当对方电话正在通话时英语播报 小学英语中一般过去时什么时候用be 动词,什么时候不用呢? 北京新东方上课多少人一个班是不是坐在后面就会影响听课效果呢?我是想学听说读写这种性质的班级的..不是4.6级 新东方的北京的名师一般是不是不去外地的新东方上课的? lt's Wednesday .对Wednesday提问 we need ( )answer----(用适当形式填空) these question 一道反义疑问句的选择题!I had a bad cold last weekend,_______?A.hadn't IB.hadn't youC.didn't ID.didn't you 一道反义疑问句选择题26.Henry never said that he was good at maths,__B_____ he?A.was B.did C.didn't D.wasn‘t 我知道用了肯定.而且这道是过去时,可是was也是过去,为什么用did 反义疑问句 选C为什么2.Nobody will believe how difficult his work has been ______?A.will he B.won’t nobody C.will they D.won’t they 2010年剑桥少儿英语二级考级时间是什么时候? They are___Jincheng Primary School.用at还是用in. 求看了之后很感动的作文!1000字或800字! It is January 1st.（对January 1st提问）________the ______? home is where she lived 什么意思 far的比较级?最高级? 反义疑问句选择题请先帮我看几道题目：1 He said Mary had done it,____?A hadn't she B hadn't Mary C didn't he D did he2 It's my son's birthday next week,and i have to do my best for that,____?A isn't it B is it C haven't I D don't I这 反义疑问句的的选择题20.I am very interested in Mark Twain's novels,_____?这道题我选BA.aren't I B.am not I C.aren't you D.are you 但是它的正确答案是A的.为什么,我区分不开A跟B的答案,因为我记得我们老师说过 My mother asked me _____-in bed A.not to read B.to not read My mother often tells me __________ in bed.(not read)空格里该怎么填? My mother said to me,"John,_____in bed." A.not read B.doesn't read C.no reading D.don't read我认为C D都可以 My mother often tells me ______(not read ) in bed. far的比较级和最高级 初中怎样变反义疑问句 【英语】far的比较级和最高级.如上 初中反义疑问句You must have made a mistake,haven’t you?　　They must have seen the film last week,didn’t they?为什么同样是表推测的完成时,第一个用have,第二个用did 有关友谊的名言警句 问一个初中反义疑问句he is doing his homework,isn't he?还是isn't him?