复合不定代词somebody ,something ,anything, nothing ,everything, everybody等是由some , any ,no ,every, 加上body, thing 构成的,叫做复合不定代词,在句子中当单数使用。
somebody, something, someone 一般用于肯定句中;anything, anybody,anyone一般用于疑问句、否定句和条件状语从句中。修饰复合不定代词的定语,应放在它们的后面。如：Hey,Lily. There is someone outside the door. /Did you meet anyone when you came to school last Sunday?/He has nothing much to do today.
one与ones用来代替上文的一个或多个人或事物,前面可以加冠词、形容词、指示代词、which等。如： Which jacket would you like, this one or that one?
so可以代替一件事情,作句子的宾语或表语。如： I dont think so. / He lost a book. So did I.
a lot of、lots of、a number of、a great deal of、plenty of的区别：五个名词+介词短语都表示大量,许多,a lot of既可以修饰不可数名词也可以修饰可数名词的复数形式,可以相应地换为much和many;plenty of足够、大量,既可以修饰不可数名词也可以修饰可数名词的复数形式。 a number of / large numbers of只可以修饰可数名词复数形式可以换为some、many、a lot of、plenty of。 a great deal of只可以修饰不可数名词可以换为much。
如：A lot of people think that time is money. / I dont have to do it in a hurry because I have plenty of time. / I have a number of letters to write today. / I spend a great deal of time/money on shopping.
none、no one、nobody的区别：no one和nobody都表示没有人,仅指人,后面不跟of 短语,作主语时谓语用单数形式;none表示没有一个人/物,可指人也可以指物,后面可跟of短语,作主语时谓语可用单数也可用复数。如：No one knows how he managed to get the ticket. / Nobody handed in his/their composition yesterday. / None of my friends came to see me that day.