题目内容：

英语单项选择语法专题的几个问题
1、He hid himself behind the door______he still could see what would happen to his classmate.
A.there B.which C.from which D.from where
2、They have a bridge to have ________ rebuilt.
A.somebody B.it C./ D.that
3、 ___________ either you or I to look after her?
A.Am B.Is C.Are D.Should
4、The family has been _________ the lost child for nearly a month.
A.in a long search for B.searching for C.in a long search of D.searching
请逐题给出解析.