We should keep rivers .......
clean.
......... is the place the fresh river water mixes with the salty ocean water.
Estuary
When rivers fall from the mountains, they form a ........
waterfall.
The Huang He River often floods, so people call it "............."
China's Sorrow
............ is on the border of Brazil and Argentina.
The Iguaçu River
The longest river in North America is ..........
the Missouri River.
The longest river in Asia is ............
The Yangtze River.
The ............ begins in Canada and empties into the Bering Sea.
Yukon River
When large rivers bring a lot of soil and sand with them, it creates a ........
delta.
When people dump waste into rivers, it causes .............
river pollution.
........... forms at the border of USA and Canada.
The Niagara River
A river always flows into the .....
sea.
The largest river in North America is ..........
the Mississippi River.
Filthy water makes us .......
sick.