1.   They poke croaks from the frogs and push rivers downstream.

2.   Flooding on the swollen Mississippi River pushed downstream Thursday, inundating basements and streets as workers and residents in rushed to shore up dikes and build sandbag levees.

3.   Instead of skimmers and absorbent boom, workers in boats scraped the surface with spades, while others shoveled oil or pushed it downstream with wires.

4.   The rocks rolled into raging rivers that pushed them downstream into houses and cars.