请适当解析~As soon as he comes back,I'll tell him when--and see h

1. As soon as he comes back, I'll tell him when__and see him
A You will come B you come 答案A 但是我觉得是B 主将从现不是吗?
这里的答案A是说,他一回来,我就会告诉他,你将什么时候来看他,显然你已经决定什么时间来看他,这个人只是转达
2. Hurry up! Alice and Sue are waiting for you at the school gate.
-Oh! I thought they _______ without me.
a.went b.are going c.have gone d.had gone 答案D 这个为什么不选C,是虚拟语气吗?
这里不是虚拟语气.我以为她们不等我已经走了呢.这个thought就是过去,原以为,不是虚拟
3. What were you up to when your parents came in?— I＿＿for a while and＿＿some reading.
A. was playing； was going to do B. played； did
C. had played； was going to do D. had played； did
答案是C 为什么不是A呢?
这里的when your parents came in是过去的动作,因此是这之前已经玩了一会儿,要用过去完成,发生在过去某时间之前的动作,而当时（他们进来时）我正在读书,was doing some reading
4. Her Bag, ( ) she put all her books, has not been found..
A Where B in which (选B 为什么不是A?）
这里强调she put all her books in the bag
而不只是where放书的地方,强调她把书放到了那个包内