1.   Ralph tried to sound hearty and enthusiastic, but his voice struggled from him like a half-drowned river rat.

2.   And so, for now, he plays the stoic river rat.

3.   Now the river rats have become hill people.

4.   One of the joys shared by river rats is auditory.

5.   Our first paddling trip was pleasant and uneventful -- we returned feeling like true river rats.

6.   Some residents call themselves river rats.