subject / course / CL:門|门[men2] / class / lesson / CL:堂[tang2],節|节[jie2] / to levy / tax / form of divination
课
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果
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讠
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Karl Marx (k) notices an advertising column (讠) in the elevator's bathroom (e4). He decides to teach these capitalists a lesson (课) and throws grapes (果) at the ads, messing them all up. That'll teach them!