Lesson 6. 
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* Problem 1.
1. We are students.
2. You are a teature.
3. You are teachers.
4. They are my friends.

* Problem 2. 
1. You are a doctor.
2. We are good friends.
3. She is my sister.
4. They are my brothers.
5. Tom and Jane are high school students.

* Problem 3.
1. Are you brother?
	Yes, We are.
2. Are they students?
	No, they aren't.
3. Are you a teacher?
	Yes, I am.
4. Are you and she tennis players?
	No, we aren't. We are table tennis players.