water can change from one form to anotheer. the heat of the sun evaporates water from the oceans, seas, rivers and lakes. the heat also evaporates water from the ground and from plants and animals. water vapour is formed. this forms clouds in the air.
when the clouds come near a mountain, they are forced to rise. as the clouds rise, they are cooled. the higher they rise, the more they are cooled. this causes more and more water vapour to condense. in this way, the tiny drops of water in the clouds get bigger and bigger until they are heavy enough to fall to the earth as rain.
some rain water which falls on the earth is again evaporated. some of it sinks into the ground. it may be used up by thirsty plants. it may reach a well or a spring. most of the water goes back to the rivers, seas and oceans. this process then starts all over again. this process is called the water cycle.
2016年中考英语词组辨析:towards/ to / for
2016年中考英语词组辨析:ache/pain
2016年中考英语词组辨析:problem/ question
2016年中考英语词组辨析:why not/ why don’t
2016年中考英语词组辨析:also/ as well/ too/ either
2016年中考英语词组辨析:talk with/ talk of/ talk on/ talk about
2016年中考英语词组辨析:about/ on
2016年中考英语词组辨析:personal/ personnel
2016年中考英语词组辨析:another/ the other/ other/ others/ the others
2016年中考英语词组辨析:worth/ worthy
2016年中考英语词组辨析:till/ until
2016年中考英语词组辨析:sound/ voice/ noise
2016年中考英语词组辨析:quite / very/ too
2016年中考英语词组辨析:alive/ living/ the living/ live/ dead
2016年中考英语词组辨析:a bit/ a little
2016年中考英语词组辨析:thanks for/ thanks to
2016年中考英语词组辨析:accept/receive
2016年中考英语词组辨析:after/behind
2016年中考英语词组辨析:answer/ reply
2016年中考英语词组辨析:that/ who/ which
2016年中考英语词组辨析:on time/ in time
2016年中考英语词组辨析:treat/ heal
2016年中考英语词组辨析:above/over/on/upon
2016年中考英语词组辨析:space/ universe
2016年中考英语词组辨析:say/ speak/ talk/ tell
2016年中考英语词组辨析:anyone/ any one
2016年中考英语词组辨析:any/ some
2016年中考英语词组辨析:so/ such
2016年中考英语词组辨析:across/through/ over
2016年中考英语词组辨析:surprise/ surprising/ surprised
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