进退

进退	jìn tuì	to advance or retreat / knowing when to come and when to leave / a sense of propriety
进	jìn	to go forward / to advance / to go in / to enter / to put in / to submit / to take in / to admit / (math.) base of a number system / classifier for sections in a building or residential compound
退	tuì	to retreat; to withdraw / to reject; to return (sth) / to decline