一群の渡り鳥が南の空へ飛んでいった。
A flock of migrating birds flew off toward the southern sky.
駅前に一群の若者が集まって騒いでいた。
A crowd of young people had gathered in front of the station and were making a racket.
草原の向こうに鹿の一群が見えた。
A herd of deer could be seen across the grassland.