He often helps me.
Who is at the door? It's me.
The bicycle belongs to Tom and me.
出现并列主语或宾语时，其排列顺序为：单数时是第二、第三、第一人称（简称231）即you，he and I或you，her and me；复数时是第一、第二、第三人称（简称123）即we，you and they或us，you and them。
2. 物主代词：形容词性物主代词作定语，后加名词；而名词性物主代词等于形容词性物主代词加名词。如： This is my book. = This book is mine.
Your pen is blue. Mine is blue,too.
May I use your pen? I've lost mine.
She is a classmate of his.
The bike is hers.
Help yourself to some cakes.
I can look at myself in the mirror.
They should think more of the public health than themselves.
We do homework by ourselves.
I myself go to the airport to meet my uncle.
What's this(that)? It's a book.
What are these(those)? They are books.
（1）指物：It's a robot.
（2）指自然现象： It's raining now, but it will be fine soon.
（3）指时间：What time is it? It's 8 o'clock.
（4）指距离：It's twenty minutes' walk.
（5）作形式主语：It's important for us to fight pollution.
It took me half an hour to finish the work.
It's kind of you to say so.
（6）作形式宾语： We think it necessary to relax from time to time.
There are some pens on the desk.
There aren't any pens on the desk.
Are there any pens on the desk?
Some are Chinese. Others are English.
Would you like some drink?
Do you know any of her friends?
If you have any questions, you can ask me.
2）复合不定代词：something， anything，nothing，everything，somebody，anybody，nobody，everybody，someone，anyone，no one，everyone，somewhere，anywhere，nowhere，everywhere这些不定代词都作单数，表示“某物”、“某人”、“某地”。
Someone is waiting for you.
No one is in the classroom.
Have you got anything to say?
Did you see anything else in the classroom?
I’ve got something interesting to tell you.
There's nothing new in the newspaper.
3）a few，few，a little，little前两者修饰可数名词，后两者修饰不可数名词。few，little表示否定，意思是几乎没有；a few，a little表示肯定，意思是还有几个、有一点。如：
There is still a little time left, you needn't hurry.
I can't buy anything because I have little money on me.
4）both（两者都，复数），all（三者以上都，复数），neither（两者都不，单数），none（三者以上都不，单复数），either（两者中的一个，单数），both...and， neither...nor， either...or
Both of the twins are doctors.
All of them are honest.
Neither of them is a doctor.
None of them is/are honest.
Both Li Ping and I are students.
Neither Li Ping nor I am a student.
on both sides of the river
on either side of the river
Both of them are teachers.
改成否定句是： Neither of them is a teacher.
All of us are students.
改成否定句是： None of us is a student. 或： None of us are students.
5）one ...the other(s)表示一个……其余的……，是有范围的；some...others 表示一些……另一些……，是无范围的；another 表示很多中的另一个，再……个。如：
He has two brothers. One is an engineer, the other is a writer.
Some like football. Others like basketball.
Some books on the shelf are in Chinese, the others in English.
She will be in hospital for another two weeks.（她将在医院再住两星期。）