1、The brave young man want__north and took __
active part in the revolutionary work there.（c)
A.the...a B.to...an C./...an D./.../

2.I assure you that you can have __good time in space.It must be your __best choice. (B)
A./...the...the B.a.../.../
C./.../...the D.a...the.../

3.When on__earth are you going to __hospital?
You've caurht such__bad cold. (D)
A./...the.../ B.the...the.../
C./...the...a D./.../...a

4.__handicapped student as she is,she often helps to clean their classroom after __school.(C)
A.A.../ B.A...the C./.../ D./...the

5.The method has proved__very effective and it is worth __ (A)
A.to be ...adopting B.being...being adopted
C.to be ...being adopted D.to have...adoption

6.I don't reget __her what I thought ,even if it
__her. (C)
A.telling...will hurt B.to tell...will hurt
B.having told...hurt D.to have told...hurted

详细地解释一下原因。

1,want这个词是否拼写错误？take a part in是一个固定短语，“参加、入”。
2，have a … time也是个固定短语，“开心、高兴”之意。有物主代词your修饰，最高级前不再加冠词。
3，on earth“究竟、到底”的意思，going to hospital“去看医生，入院”之意，都是抽象的意义概念，不加冠词，也可以看成是固定搭配。caurht a bad cold“患感冒”的意思。
4，前一空是as引导的让步状语从句，倒装时，可数名词前不加冠词；后一空是说“放学以后”，抽象意义概念，不加冠词。
5，prove为系动词，其后要接形容词作表语，或加to be短语；is worth后，要加主动形式的动词+ing形式。
6，reget后加动词的ing形式，表示“悔恨、后悔所做过”事情。后面一空的动词hurt，原型、过去式，过去分词形式都是一样的。