힘이 · 힘을
strength, power, energy
Example
아침을 못 먹어서 힘이 하나도 없어요.
I couldn't eat breakfast, so I have no energy at all.
Word parts
The base of 힘들다 (hard, tiring) and 힘내다 (to cheer up).
Good to know
힘내세요! is the classic way to say 'Hang in there!' or 'You can do it!'