Unit 4 Astronomy：the science of the stars
Period 1 Grammar points.
一．语法要点
主语从句：在复合句中作主句的主语的从句叫主语从句。引导主语从句的词有连词that, whether；连接代词who, what, which；连接副词when, where, how, why等。
Eg: Which team will win the match is still unknown.
主语从句放在句首，句子常显得笨重，因此一般把它放到句子后面，前面用引导词”it”来作主语。
Eg: It’s strange that he didn’t come yesterday.
二．重点难点
1．Nobody knew that it was going to be different from other planets going to be different from other planets going round the sun.
going round the sun 为现在分词短语定语，表示一般的动作。
Eg: Men breaking the law will be punished.
现在分词短语，也可表示进行的动作
2. Weather life will continue on the earth for millions of years to come will depend on whether this problem can be solved.
for millions of years to come 中不定式to come 作定语，与前面的名词有逻辑上的主谓关系。
Eg: She is the last person to tell lies.
3．The problem was that the earth became violent because it was not clear whether the solid shape was to last or not.
The problem was that …, that 引导表语从句，that 只起连接作用，无意义，但不能省略。
Eg: The trouble is that we are short of money.
4．As the earth cooled down, water began to appear on its surface.
as conj. 随着，在…期间；由于，因为；尽管，即使；当…的时候；像…一样
5. That made it possible for life to begin to develop.
it 是形式主语，真正的主语是不定式to begin to develop.
Eg: He thinks it’s his duty to help others.

三．功能句型
指示（Introductions）
Please look at/ listen to … Please pay attention to ...
Please check that … Make sure you …
Don’t forget to … Watch out for …
You need … You’d better …
You must/mustn’t …
四. 重点单词及短语
单词
① atmosphere n. 大气，空气，气氛
a friendly atmosphere 友好的气氛
atmospheric adj. 大气的，有气氛的
② violent adj. 剧烈的，厉害的；（人）暴戾的；（感情、言语）激昂的，激烈的
violence n. 剧烈，暴行
violently adv. 激烈地，粗暴地
③ solid adj. n. 固体的；实质的；纯粹的；结实宾；牢靠的，稳固的
④ explode vt. vi. 爆炸，使爆炸；感情爆发；驳倒，推翻
explosion n. 爆发，爆炸
explosive adj. 爆炸性的，爆发性的
⑤ surface n. 外表，表面；adj. 表面的，外表的；vt. vi. 浮出水面，给…装上表面
⑥ dissolve vt. vi. 使溶解，溶解；解散，消除，解除
dissolution n. 解散，溶解
⑦ harmful adj. 有害的
harm n. v. 危害，伤害
harmless adj. 无害的
harmlessness n. 无害，无恶意，天真无邪
harmfully adv. 有害地
harmlessly adv. 无害地
⑧ spread vt. vi. n. （使）张开，伸展，扩张；涂；散布，传播；（使）蔓延
⑨ exist vi. 在，存在，生存
existence n. 存在；生活，生存
⑩ mass n. 团，块，堆，众多，大量；pl. 群众，民众；质量

短语
in time 迟早，最后 in time for sth./to do sth. 及时，不迟
prevent … from 阻止某人做某事（from 有时可省略，但在被动说现语态中不能省）
depend on/up sth. 依靠，指望；相信；取决于
cheer up 使某人高兴或更快乐
now that 既然，由于
break out 突然发生，逃出某地
make sense of … 理解，弄懂，有道理，有意义，理智的