高一英语必修三Unit4课文主语从句Microsoft PowerPoint 幻灯片

unit 4 Astronomy： the science of the stars
How Life Began On The Earth
找出课文中的主语从句
主语从句
What itwas wasto to become was uncertain until What it become betweeen 4.5 and 3.8 billion years ago when the intoa asolid solid globe. when thedust dust settled settled into globe (L6-8) 定语从句 随后它会变成什么没人能知道，直到38~45亿 年前，这团尘埃才慢慢地形成一个固体的球状 物。
主语从句
Sowhether whether life will continue life will continue on on thethe earth for millions years to tocome come will earth for millions of years depend on whether this problem can be solved.（L50-51） 翻译：所以，在未来的数百万年中，生命 能否在地球上延续取决于这个问题能否得 到解决。
翻译：更为重要的是，地球冷却了下来， 地球的表面就开始出现了水。
It 是形 式主语
It was not immediately obvious
主语从句
that water was to be fundamental that water was to be fundamental to the of life. (L18-20) todevelopment the development of life. 句子可改为：
It 是形式 主语
It was not clear
主语从句
whether the shape would last or not. (L9-10) whether the shape would last or not 句子可改为
Whether the shape would last or not was not clear.
That water was to be fundamental to the development of life was not immediately obvious. 水对生命的发展会起到关键作用，这一点在 当时并不明显。
主语从句
Whatmany manyscientists scientists believe What believe is that the continued presence of water allowed the earth to dissolve harmful gases and acids into the oceans and seas.
翻译：不知道这个固体形状是否会继续存在下去。
主语从句
What is What iseven evenmore more important important is that as the earth cooled down, water began to appear on its surface.（L13-15）
（L21-25）
翻译：很多科学家相信，由于地球上长期 有水存在，使地球得Байду номын сангаас把有害气体和酸性 物质溶解在海洋里。
主语从句
Why disappeared still Whythey they suddenly suddenly disappeared remains a mystery.(L41-42) 它们为什么会突然灭绝至今仍是个谜。