英语中的不定代词和复合不定代词没有明确的指代对象，如some, any, no, every等。复合不定代词由两个或更多的单词组成，如someone, anybody, nothing等。它们可以作为主语、宾语、表语或介词宾语，但不能与否定词一起使用。掌握这些词的用法可以提高英语理解和表达能力。
复合不定代词由两个或两个以上的单词组成，可以用来代替名词。下面是一些常见的复合不定代词及其用法：
- someone/somebody/something 用来指代某个人或某个事物，例如：
- I saw someone in the park.
- Somebody left their umbrella in the classroom.
- Is there something you want to tell me?
- anyone/anybody/anything 用来指代任何人或任何事物，例如：
- Does anyone know the answer to this question?
- Anybody can join the club.
- You can ask me anything.
- no one/nobody/nothing 用来表示没有人或没有事物，例如：
- No one came to the party.
- Nobody is perfect.
- There is nothing to worry about.
- everyone/everybody/everything 用来指代所有人或所有事物，例如：
- Everyone is invited to the wedding.
- Everybody loves a good story.
- Everything happens for a reason.
- something/someone/anything/anyone + else 用来指代除了已经提到的人或事物之外的其他人或事物，例如：
- I already have plans with someone else.
- Is there anything else you need help with?
在使用复合不定代词时，需要注意以下几点：
- 不定代词不能与否定词一起使用，例如：nobody can't, nothing isn't等等。
- 在句子中，复合不定代词可以作为主语、宾语、表语或介词宾语。
