榆木疙瘩

榆木疙瘩	yú mù gē da	lit. knot on an elm tree (idiom) / fig. blockhead; dunce
榆	yú	elm
榆木	yú mù	elm / elmwood
木	Mù	surname Mu
木	mù	(bound form) tree / (bound form) wood / unresponsive; numb; wooden
疙	gē	pimple / wart
疙瘩	gē da	swelling or lump on skin; pimple / knot; lump / preoccupation; problem
瘩	dá	sore / boil / scab
瘩	da	used in 疙瘩