流于形式

to become a mere formality

to flow / to disseminate / to circulate or spread / to move or drift / to degenerate / to banish or send into exile / stream of water or sth resembling one / class, rate or grade

to change (for the worse)

to go / to take / sentence-final interrogative particle / variant of 於|于[yu2]

(of time or place) in; at; on / (indicating any indirect relation) to; toward; vis-à-vis; with regard to; for / (indicating a source) from; out of / (used in comparison) than / (used in the passive voice) by

to appear / to look / form / shape

outer appearance / form / shape / formality / CL:個|个[ge4]

type / form / pattern / style