If a person doesn't go to the bathroom for a few days, he'll feel uncomfortable. This stuff just sits there on the bottom, so naturally the river stinks. "
人要是幾天不上廁所，肚子積了一大堆排洩物，一定很不舒服；淡水河也是如此，河底淤積了這麼多爛泥，影響她正常的流速與排洩，自然就會發臭啊！」