[求助]请教几个不确定的词组用法！！

1。distinguish A and B 和 distinguish A from B 是都可以，还是在含义上有不同，或使用上有优先级别？

2。just as....., so.....中so一定要加么？为何有些题目中是不加的呢？

3。He does more than +V 的这个V是用动词原型还是第三人称单数呢？

谢谢各位达人啊！！！

第一题的解释是斑竹carolhide曾经在我问的一道题里做的解答：（我觉得discriminate 和distinguish的这两种用法意思差不多）

参见大全382.

discriminate between…and…的范围比discriminate…from…广。后者只能之比较的两物是完全对立的。

genuine diamonds和imitation diamonds，不是等同相反的两个概念：真的应对假的，而imitation只能认为是假的一种。似乎ETS更喜欢discriminate between…and…
   

Longman 中的解释
   

discriminate between: to recognize a difference between things.

Eg: It is sometimes difficult to discriminate between edible and poisonous mushrooms.

discriminate sth .from

eg. You must learn to discriminate fact from opinion.

A test is useful for discriminating those students who have reached a higher level from those at a lower.

The parties have become so similar it is difficult to discriminate Republicans from Democrats.

the process of learning to discriminate fact from opinion

Small children can't distinguish right from wrong

第二题，我认为如果just as 放在前面，后面跟着作比较的句子要用so，否则这个句子没有连词孤立的放在那儿，但如果just as放在后面，前面那个句子当然可以不加so，没来由

第三题，V用动词原形

如果看到有更确切的解释或者反例，别忘了通知我一声啊

he does more than V

如果V用原形，V跟哪个平行呢？（题个小问题~呵呵）

可能有context更好分析一点~

Many thanx!

I'll let u know should there be any update!