选择正确的语句表达,将其序号填入题前括号里。
( )1.

A. We have three new teachers.
B. We have two new teachers.
C. We have two new pupils.
( )2.

A. Sit in the first row, please.
B. Sit in the second row, please.
C. Sit in the third row, please.
( )3.

A. I'm Chinese.
B. I'm Canadian.
C. I'm American.