汗牛充栋

lit. enough books to make a pack-ox sweat or to fill a house to the rafters (idiom); fig. many books

see 可汗[ke4 han2], 汗國|汗国[han2 guo2]

perspiration / sweat / CL:滴[di1],頭|头[tou2],身[shen1] / to be speechless (out of helplessness, embarrassment etc) (Internet slang used as an interjection)

ox / cow / bull / CL:條|条[tiao2],頭|头[tou2] / newton (abbr. for 牛頓|牛顿[niu2 dun4]) / (slang) awesome

to fill / to satisfy / to fulfill / to act in place of / substitute / sufficient / full

sufficient; full / to fill / to serve as; to act as / to act falsely as; to pose as

classifier for houses or buildings / ridgepole (old)