long white smear

例句：

1. 1.The long white smear on the wall was caused by a leaky pipe.
   墙上的长白沫是由一个漏管造成的。
2. 2.The long white smear on the floor was caused by a spilled drink.
   地板上的长白沫是由一个洒落的饮料造成的。
3. 3. The long white smear on the window was caused by a strong wind.
   窗户上的长白沫是由一阵强风造成的。