To express that an action is difficult to do, the auxiliary adjective にくい may be appended to the verb stem
Properties of にくい as an auxiliary adjective include:
- Used with more physical verbs than がたい.
- Used with both verbs that do and do not involve intention.
- More objective than づらい.
Further Reading
- Describing actions as easy or hard – Tae Kim’s Japanese grammar guide (guidetojapanese.org)
- V + やすい & V + にくい ( = V + yasui & V + nikui) (maggiesensei.com)