It's up to the teacher to provide a variety of types of input in the classroom.

教师负责在课堂上提供各种各样的信息资源。

《柯林斯英汉双解大词典》

There was complete anarchy in the classroom when their usual teacher was away.

任课老师不在时，班上一片混乱。

《牛津词典》

A teacher who merely has an off day in the classroom cannot be dismissed for incompetence.

一个教师偶尔在课堂上发挥欠佳不能被看成不称职而遭免职。

《柯林斯英汉双解大词典》

And because we know that from the moment our kids enter a school, the most important factor in their success -- other than their parents -- is the person standing in front of the classroom, the teacher.

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In the classroom, a teacher in this category "demonstrates minimal understanding of the subject, " according to the school system.

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In first grade, whenever someone made a mess in the classroom, the teacher would ask a student to get the janitor.

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