頑張る, がんばる
Conjugated: がんばりましょう
Godan verb, Intransitive
1. to persevere, to persist, to keep at it, to hang on, to hold out, to do one's best
2. to insist that, to stick to (one's opinion)
3. to remain in a place, to stick to one's post, to refuse to budge
いや、頑張ればできるよ。