人不可貌相

you can't judge a person by appearance (idiom) / you can't judge a book by its cover / often in combination 人不可貌相，海水不可斗量[ren2 bu4 ke3 mao4 xiang4 , hai3 shui3 bu4 ke3 dou3 liang2]

person; people / CL:個|个[ge4],位[wei4]

no; not so / (bound form) not; un-

cannot / should not / must not

cannot; should not; must not

can / may / able to / to approve / to permit / to suit / (particle used for emphasis) certainly / very

used in 可汗[ke4 han2]

appearance

appearance (esp. superficial) / looks / to judge a person by appearances

each other / one another / mutually / fret on the neck of a pipa 琵琶[pi2 pa5] (a fret on the soundboard is called a 品[pin3])

appearance / portrait / picture / government minister / (physics) phase / (literary) to appraise (esp. by scrutinizing physical features) / to read sb's fortune (by physiognomy, palmistry etc)

you can't judge a person by appearance, just as you can't measure the sea with a pint pot (idiom)