疑问代词
1. 疑问代词即指who, whom, whose, which, what等用于引出特殊疑问句的代词。它们在句中可用作主语、表语、宾语、定语等。
如：
What did she say? 她怎么说?(what作say的宾语)
Which are our seats? 哪些是我们的座位?(which作表语)
What are you worrying about? 你为什么事烦恼?(what作about的宾语)
注意：1. who和whom 只用作主语、宾语和表语，不用作定语;what, which, whose 则既可用作主语、宾语和表语，也可用作定语。
2. what与 which的用法区别：当选择的范围较明确时，用 which;当选择的范围不明确时，用 what。
如：
Which color do you like, red, black or white? 红色、黑色和白色，你喜欢哪种?
What color is your car? 你的汽车是什么颜色的?