1. 先行词既有人又有物
I still remember the day and the people that we we visit last year.
2. 当先行词被序数词修饰时
This is the first book that I bought this year.
2. 当先行词被形容词最高级修饰时
This is the best movie that I've ever seen.
3. 当先行词被the only/the very/all/little/few/much修饰
He is the only person that can help you.
4. 当先行词是 all, little,few,much,everything,anything,something,nothing等不定代词时
I have something that I want to tell you.
5. 当先行词被all,any,few,little,much,none,only,no等词修饰时
He told me all that he knew.
