讲台上的安眠药课桌上的睡觉王
[jiăng tái shàng de ān mián yào kè zhuō shàng de shuì jué wáng]
A sleep-inducing lecturer on the platform; King of sleeping at the desk. This refers to a boring teacher or class, and implies someone either easily falling asleep in class or making humorous reference to the droning lectures putting students to sleep.