变质作用

metamorphism (geology)

to change / to become different / to transform / to vary / rebellion

to degenerate; to deteriorate / (of food) to go bad; to go off / (geology) metamorphism

character / nature / quality / plain / to pawn / pledge / hostage / to question / Taiwan pr. [zhi2]

worker / workshop / (slang) troublesome / high-maintenance (person)

to do; to engage in / to write; to compose / to pretend; to feign / to regard as; to consider to be / to be; to act the part of / to feel (itchy, nauseous etc) / writings; works

to act on / to affect / action / function / activity / impact / result / effect / purpose / intent / (suffix) -ation, -tion etc, as in 抑制作用[yi4 zhi4 zuo4 yong4], inhibition

to use / to employ / to have to / to eat or drink / expense or outlay / usefulness / hence / therefore