The Sun is the main source of energy that provides _____ to the Earth.

• heat

• wind

• food

• oxygen

The heat gained causes water on Earth's surface to become______.

• cold

• hot

• icy

• rain

The water will _________ into the air as water vapour.

• boil

• melt

• evaporate

• condensate

Accumulated water vapour will form _______.

• water

• strong wind

• rain

• clouds

The clouds will become _______ when more water vapour combined.

• heavier

• darker

• beautiful

• lighter

In a period of time, the clouds will ________ to become rain.

• freeze

• evaporate

• condense

• melt

_____ will flow back into lakes, river and seas on the Earth's surface.

• Clouds

• Ice crystal

• Rain water

• Oxygen

This process repeats thus forming the ________.

• life process

• water cycle

• natural process

• cloud and rain

Water cycle is the _______ from the Earth's surface to the air and to the surface again.

• movement of the Earth

• movement of clouds

• movement of air

• movement of water

In summary, the natural water cycle involves the processes of _______ and ________.

• evaporation; condensation

• evaporation; melting

• boiling; condensation

• freezing; melting