Most people would describe water like a colorless liquid. They __1__would know that in very cold conditions it becomes a solid calledice 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.$ m$ Z, F* [2 E- D0 ]
This is equally true of the solid called ice and the gas called steam.
2 v9 N- Y9 _* _; L: @- w, L: KChemically there is no difference between the gas, the liquid, andthe 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 asgases or as liquids or as solids. We may normally think of iron as asolid, 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.
0 t+ a4 L9 F8 xEveryone 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 becausewater 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 theminto 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__参考答案及解析:# ^5 u Q$ I+ M$ {# ~
1. 改like为asdescribe sth as sth 是把……描述成……的意思。
\" k2 N$ @. I. E) z2. 改heating为heated在时间,条件,让步等状语从句中,当从句主语和主句主语是一致的时候,可以将从句的主语和be的变化形式省略。
5 e/ G& u- G, X4 V3. 改with为ofbe composed of 意思为“包括,由……组成”
, q$ i. A2 d3 O$ m4 Y4. 改is made up 为 are made upwhich 指代上文中的 the gas, the liquid,and the solid,表示复数概念,所以要用are5. 将第一个will去掉在时间条件状语从句和条件状语从句中要用现在时表示将来时。
2 q% @% k3 `( y% s2 @) U6. by改为whenwhen warm 相当于 when it is warmed7. 改so为such8. 改with为to短语familiar to 后面才能接“某人” familiar with 是接sth9. 改requiring为required过去分词短语作后置定语时,和被修饰的名词时逻辑动宾关系。: m8 o; i$ }; X* G; d; Q
10. have 后加 been动词give和主语three states 是动宾关系 |