这有几个例题，不要只说下面几个题的思路，最好写出通用的思路。
2。There's a feeling in me____we'll never know what a UFO is-not ever.
A.that B.which C.of which D.what
58。Dandy left word with my secretary____he would call again in the afternoon.
A.who B.that C.as D.which
7.There is much chance___Bill will recover from his injury in time for the race.
A.that B.which C.until D.if
16.A warn thought suddenly came to me ____I might use the pocket money to buy some flowers for my mother's birthday.
A.if B.when C.that D.which

所有的题都应选择 THAT.以上四句话中,空格后的从句都是定语从句且直接修饰一个事物(feeling, word, chance, and thought),所以事实上只能在 THAT 和 WHICH 里面选.但在这里有一个亲疏关系问题,用 THAT 起头的定语从句与被修饰的名词之间的关系比用 WHICH 起头的定语从句与名词的关系近,也就是说,如果缺少一个由 WHICH 起头的定语从句,那么人们还能辨别出所指的事物是哪一个,而缺少了由 THAT 起头的定语从句,就无法知道究竟是哪一个事物了.这几句话都是没有后面修饰,就不知道感觉了什么,说了什么,有什么样的机会,及有什么想法.所以都应该选 THAT.