硬骨頭

resolute individual / a hard nut to crack / tough mission / difficult task

hard / stiff / strong / firm / resolutely / doggedly / good (quality) / able (person) / (of food) filling / substantial

bone

bone / CL:根[gen1],塊|块[kuai4] / moral character / bitterness / Taiwan pr. [gu2 tou5]

head / hair style / the top / end / beginning or end / a stub / remnant / chief / boss / side / aspect / first / leading / classifier for pigs or livestock / CL:個|个[ge4]

suffix for nouns