暴雨过后，山坡上的水流冲走了表层的土壤。

The heavy rain caused ___runoff from the hillside to wash away the topsoil.

由于两位候选人票数相同，下周将举行决胜选举。

Since the two candidates tied, there will be a ___runoff next week.

暴雨过后，地表径流将泥土冲入了附近的小溪。

After the heavy rain, the ___runoff carried soil into the nearby creek.