pebble

n.鹅卵石; 砾石vt.用卵石铺; 用石子扔; 使纹理粗糙 复数：pebbles 牛津词典 noun 鹅卵石；砾石a smooth, round stone that is found in or near water 柯林斯词典 鹅卵石；砾石A pebble is a small, smooth, round stone which is found on beaches and at...