There is no doubt that all this puts a large on a teacher with a large number of classes.

问题补充：

There is no doubt that all this puts a large on a teacher with a large number of classes.

A. tax

B. catastrophe

C. sense

D. burden

答案：

A. tax

B. catastrophe

C. sense

(答案→)D. burden

解析：tax 税,税款,税金; catastrophe大灾难,大祸; sense感觉,意义,理性;burden担子,负担。a large burden 一个很大的负担。