干净

Keep your language clean!

He has sticky/itchy fingers.

wipe out the enemy

clean clothes

have a foul mouth; be foul-mouthed

scrub one's mouth with a handkerchief

clean off a blackboard

rub/scrub sth clean

clear off the table after dinner

wash the towel clean

clean up the kitchen; sweep the kitchen clean; give the kitchen a good cleaning

be clean in one's person; be a clean person; be cleanly

wipe out the enemy

He is very concise in writing.