Most people would describe water like a colorless liquid. They __1__
would know that in very cold conditions it becomes a solid called
ice and that when heating on a fire it becomes a vapor called steam. __2__
However, water, they would say, is a liquid. We have learned that water consists of molecules composed with two atoms of hydrogen __3__
and one atom of oxygen, which we describe by the formula H2O.
This is equally true of the solid called ice and the gas called steam.
Chemically there is no difference between the gas, the liquid, and
the solid, all of which is made up of molecules with the formula H2O. __4__
This is true of other chemical substances; most of them can exist as
gases or as liquids or as solids. We may normally think of iron as a
solid, but if we will heat it in a furnace, it will melt and become a __5__
liquid, and at very high temperatures it will become a gas. Nothing
very permanent occurs when a gas changes into a liquid or a solid.
Everyone knows that ice, which has been made by freezing water,
can be melted again by warmed and that steam can be condensed __6__
on a cold surface to become liquid water. In fact, it is only because
water is so a familiar substance that different names are used for __7__
the solid, liquid and gas. Most substances are only familiar with __8__
us in one state, because the temperatures requiring to turn them __9__
into gases are very high, or the temperatures necessary to turn them
into solids are so low. Water is an exception in this respect, which
is another reason why its three states have given three different names. __10__
參考答案及解析:
1. 改like爲as
describe sth as sth 是把……描述成……的意思。
2. 改heating爲heated
在時間，條件，讓步等狀語從句中，當從句主語和主句主語是一致的`時候，可以將從句的主語和be的變化形式省略。
3. 改with爲of
be composed of 意思爲包括，由……組成
4. 改is made up 爲 are made up
which 指代上文中的 the gas， the liquid，and the solid，表示複數概念，所以要用are
5. 將第一個will去掉
在時間條件狀語從句和條件狀語從句中要用現在時表示將來時。
6. by改爲when
when warm 相當於 when it is warmed
7. 改so爲such
8. 改with爲to
短語familiar to 後面才能接某人 familiar with 是接sth
9. 改requiring爲required
過去分詞短語作後置定語時，和被修飾的名詞時邏輯動賓關係。
10. have 後加 been
動詞give和主語three states 是動賓關係
