Oceans and rivers.

A ... is a river that flows into a larger river.

• a) well

• b) meander

• c) tributary

In the ..., the river reaches the coast.

• a) middle course

• b) lower course

• c) upper course

An ... is a body of porous rock that stores water like a sponge.

• a) iceberg

• b) aquifer

• c) underground river

The amount of water that a river carries is called the...

• a) flow.

• b) channel.

• c) source.

Oceans and seas are large bodies of...

• a) fresh water.

• b) salt water.

• c) groundwater.

Groundwater comes mainly from...

• a) icebergs.

• b) mountains.

• c) precipitation

In the ..., the water of the river flows slowly across plains.

• a) middle course

• b) upper course

• c) lower course

... are the regular rise and fall of sea levels.

• a) Waves

• b) Algae

• c) Tides

People build ... to access groundwater.

• a) reservoirs

• b) wells

• c) aquifers

In the ..., the river channel is narrow and shallow.

• a) upper course

• b) lower course

• c) middle course