英语中的代词用于代替名词，以避免重复。主要包括主格代词（如I，you，he，she，it，we，they），宾格代词（如me，you，him，her，it，us，them），形容词性物主代词（如my，your，his，her，its，our，their）和名词性物主代词（如mine，yours，his，hers，its，ours，theirs）。掌握这些代词的用法可以使英语交流更加流畅。
1. 主格代词
主格代词用于作为主语或表语，常用的主格代词有：I，you，he，she，it，we，they。
例如：
- I am a student.
- You are my best friend.
- He is a doctor.
- She is my sister.
- It is a lovely day.
- We are going to the park.
- They are playing basketball.
2. 宾格代词
宾格代词用于作为动词或介词的宾语，常用的宾格代词有：me，you，him，her，it，us，them。
例如：
- She gave me a present.
- I love you.
- He invited him to the party.
- The cat followed her.
- The ball hit it.
- They invited us to dinner.
- The teacher scolded them.
3. 形容词性物主代词
形容词性物主代词用于表示某物属于某人或某物，常用的形容词性物主代词有：my，your，his，her，its，our，their。
例如：
- This is my book.
- Is this your car?
- His mother is a teacher.
- Her house is beautiful.
- The dog chased its tail.
- Our school is big.
- Their parents are doctors.
4. 名词性物主代词
名词性物主代词用于代替名词，常用的名词性物主代词有：mine，yours，his，hers，its，ours，theirs。
例如：
- This book is mine.
- The car over there is yours.
- The house is hers.
- The cat is its.
- The school is ours.
- The bikes are theirs.
