顶岗

顶岗	dǐng gǎng	to replace sb on a workshift / to substitute for
顶	dǐng	apex / crown of the head / top / roof / most / to carry on the head / to push to the top / to go against / to replace / to substitute / to be subjected to (an aerial bombing, hailstorm etc) / (slang) to "bump" a forum thread to raise its profile / classifier for headwear, hats, veils etc
岗	gāng	variant of 冈 [gang1]
岗	gǎng	(bound form) hillock; mound / sentry post; policeman's beat / (bound form) job; post