n.沙,沙滩,沙色
vt.撒沙于,用砂纸磨光
The sand on the floor scrunched under our feet.
地板上的沙子在我们脚下嘎吱作响。
They all walked barefoot across the damp sand to the water's edge.
他们全都光着脚走过潮湿的沙地来到水边。
The sand martin is a brown bird with white underneath.
崖沙燕是一种褐羽白腹的鸟。