选择句子，补全对话。A: Welcome to our school. This is the teacher's office. This is my classroom.
B:1_____
A: Forty-five.
B: Do you have a library?
A: Yes.
B: Do you have lunch at school?
A:2_____
A: Look! This is our playground.
B:3_____
a. Cool! Your school is beautiful.
b. How many students are there in your class?
c. Yes. The canteen is on the first floor.1. b 2. c 3. a