1）there comes a time in every man's life (when he has to thi

1）there comes a time in every man's life (when he has to think)?
用which he needs 不行 因为意思不对
如果 用which 则代替先行词 a time在定从中 作宾语
本句应该 用when =during which 引导定从 在从句中作状语 意思才通顺.
2）yet no firm evidence had come to light （that）the men arrested were actually responsible.用which不可以 因为这不是定语从句 而是名词性从句 作同位语 是同位语从句 补充说明 evidence
3)do you like the book your father gave you
very much.it is exactly( the one) i want.
这个地方的the one是表语 后面是省略that的定语从句
如果用that 或者which则是表语从句 意思不通 如果是定从则缺先行词.

这是where when 等关系副词引导的定语从句，这里的when 就等于 in which，
所以你要改的话，也是in which he needs to think
这里不是定语从句，而是同位语从句，that 后面的从句应是 evidence 的同位语，因为that 从句如果直接放在evidence后面会导致主语太长，头重脚轻，所以从句放后面。
the是定冠词，用在这...

1. 先行词为life， 用关系副词引导,在从句中做状语。

3. the one 是主句的表语，关系代词that在从句中作want的宾语，省略了.

第二题不是定语从句

1）there comes a time in every man's life (when he has to think)?
which he needs 为什么不行
which he needs是“他需要时间”，意思不对的。
每个人的生命中都有着得思考的时间。
2）yet no firm evidence had come to light （that）the...