2015-2016学年人教版高中英语必修3课件 Unit 4 Astronomy--the science of the stars Language points 课件(10张)
2015-2016学年人教版高中英语必修3课件 Unit 4 Astronomy--the science of the stars Language points 课件(10张)第3页

1. What it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe. 随后它会变成什么没人知道,知道38-45亿年前这团尘埃才慢慢地形成一个固体的球状体。

1) 句中“What it was to become ” 是一个主语从句,在句中充当主语,谓语动词用单数。 2) was to become: be to do :注定要,必定会