降低效率英语

reduce the work efficiency。

用lessen~~~~~~~~~~~~~~~~~~~

There are 4 classes in the morning ,if you do not have the breafast,which will bring down your learning efficiency greatly.

to decrease the efficincacy of learning /learning efficiency

如果一定要从你给的4个里选的话，最合适的就是reduce。

是降低机器的，还是人的工作效率啊！

1There are 4 lessons in the morning.We can't concentrate on listening to the lessons if we don't have breakfast .And this will greatly reduce our learning efficiency

不知道前后句式是怎样的，试着翻译了几句，供参考：Learning efficiency is on the decline. 学习效率每况愈下Learning efficiency declines 学习效率降低了The decline of learning efficiency 学习效率的降低……