Q3:

Were it not for the fusion-powered heat and radiation that rush from its core, instead its own weight would cause a star to collapse.

1. instead its own weight would cause a star to collapse
2. instead a star would have collapsed under its own weight
3. a star would have to be collapsing under its own weight
4. a star would collapse under its own weight
5. its own weight would have caused a star’s collapse

问一下 were it not for 的用法，以前记得学过的。。

这个表示方法只能倒装么？

it在这里指代什么呢？

答案c

问一下  为啥是Ｃ　　不是选D

指代主句主语。

这个结构可以不倒装。。。

意识到前面第二个问题有点傻。。

不过我感到这里的it 可能不是指代主语

比如说，were it not for him, I would have died. 

虽然上句是我胡诌的，但是感觉上应该是符合语法的吧？

（可能也是出于这个原因把stars提前一面引起混淆）