bù​yì HSK5

difficult

不易 bù​yì
difficult adverb
not easy to do something; hard to achieve

It is no easy task to learn a foreign language in a short period of time.

unchanging adverb
fixed or constant; not subject to change

In this ever-changing era, few rules remain forever unchanged.

Frequency

Movie subtitles
1.40 per million appears in 1% of films

Details

HSK 3.0
Level 5

Sources

Definitions
CC-CEDICT
Frequency data
SUBTLEX-CH