zhè xiē / é luǎn shí / jīng guò / duō nián / chōng shuā / dōu / biàn chéng / le / guāng huá / de / luǎn yuán

这些鹅卵石经过多年冲刷，都变成了光滑的卵圆。

After years of tumbling, these pebbles have become smooth ovals.