科技
人稱代詞：
I am a student.
You are a teacher.
He is a worker.
She has a dog.
They will go to Beijing.
指示代詞：
This is Mary.
That is my coat.
疑問代詞：
what is this?
不定代詞：
Both of them are teachers.
some (of them) are doctors,some (of them) are nurse.
