相互代词：表示相互关系的词叫相互代词。
each other ,one another是相互代词,译成互相,可以通用。each other表示两者之间,而one anther表示许多人之间。它们有所有格形式each others ,one anothers。如： We must help each other when we are in trouble. / They sat there without talking to one another / each other.
疑问代词：用来提出问题的代词称为疑问代词。
1.who、whom、whose、what、which、whoever、whatever、whichever主要用于特殊疑问句中,一般放在句首。口语中也常用who代替whom作宾语,但在介词后则只能用whom。如：
Who did you invite to your birthday party? / What does she want to be when she grows up?
2.who 和whom只能独立使用,其中who可以作句子的主语、表语或动词的宾语,whom只能作谓语动词的宾语;而what、which、whose等既可以独立使用作主语、表语和宾语,也可以与名词构成疑问短语。如： Who is that man? / What colour are their hats? / Which car was made in Germany?
注意这个提问：The man in the car is my father.
Which man is your father?
3.which除了可以询问指代的情况之外,还可以针对说明人物的时间、地点、岁数、颜色、大小、状况等进行提问。如：People there live a very sad life. Which people live a sad life? / --Which hotel have you booked for your holiday?The biggest one in Haikou.
4.疑问代词不分单复数,视它所替代的人或事物决定单复数,但是通常用单数;如果修饰名词,则以名词的单复数为准。如：Who is in that playhouse? / What is that? / What are those? / What colours do they have?
上一篇： 理工类英语词汇选项(四)