gun-gun
Moving forward with strong, steady momentum — a runner pulling ahead, a plant growing rapidly, or skills improving quickly.
💡A child growing — 'The sunflower is gun-gun growing taller!'
ひまわりがぐんぐん伸びている。
The sunflower is gun-gun growing.
The runner ___ pulled ahead of everyone.
ランナーが○○前に出た。