there are 18 classrooms in our school 改同义句 ―― ―― 18classrooms in the school老感觉这题出错了.

问题描述:

there are 18 classrooms in our school 改同义句 ―― ―― 18classrooms in the school
老感觉这题出错了.

There exist 18 ciassrooms in the school. there exist=there be

We have 18 classrooms in the school.

改成:
We have 18 classrooms in the school.