在线求讲解that 和 it 指代的区别~~~！！

静默如林

OG12综合  
67.Affording stategic proximity to the Strait of Gibraltar, Morocco was also of interest to the French throughout the first half of the twentieth century because they assumed that if they did not hold it, their grip on Algeria was always insecure.

D. without that, they could never be secure about their grip on Algeria.

OG 的解释： It, not that, should be used to refer back to Morocco; could never be secure about their grip is awkward.

请问 这里 that 和 it 的指代有什么不同？？ 为什么不能用that??

Lusiazh1989

这是之前的帖子拉。。。刚好做到这题阿。。同样的问题。。感觉上用that不对，但是解释不清楚。最起码它非常wordy，因为之前有一个引导词that了。。

求大牛，讲解语法

漫漫在哪里

我从XDF寒假笔记里面看到的：
that与it的区别
（1）作代词时，that是不能“裸奔”的，而it天天“裸奔”；
(即this和that作为代词单独出现的时候，既不修饰别人，也不被别人修饰的情况）
例：  Michael bought that. ×
Michael bought that car. √
This is a book. ×
This one is a book. √
（2）it是特指，而that只能指代名词本身。
例：The weather in Beijing is warmer than that in Alaska.
  （把上句中的that换成it则指代的是weather in Beijing）
3.用that指代单数名词，用those指代复数名词；都无法指代的时候就用实体名词。

Lusiazh1989

所以这个题中。that是裸奔啦。。所以必须用it。。。
谢谢阿。。。其实我也见过这个笔记，但是完全没想起来。。。。