根据短文内容,判断正(T)误(F).

     Good morning, class (同学们). My name is Wang Gang. I'm your teacher. This is Dongdong. This is

Liu Mei. Nice to meet you.

(     )1. Dongdong is a teacher.

(     )2. Liu Mei is a teacher, too.

( )3. Wang Gang is a teacher.

( )4. They are in the classroom.

(    )5. Dongdong and Liu Mei are classmates (同学).

刚性防水屋面一般有（）组成

A、找平层

B、隔离层

C、防水层

D、结合层