The boy is very tall,so he has to sit __ __ __ __the classromm(在后面)

问题描述:

The boy is very tall,so he has to sit __ __ __ __the classromm(在后面)

in back of 。有the的是指靠在墙壁上的那面后墙。
没有the的是指教师空间的后部分。所以你该写后者。清楚了吗?呵呵

at the back of
The boy is very tall, so he has to sit at the back of the classroom.

in the back of
在教室里的后面用“in”

at the back of:在…后方〔背后〕