求助语法题

wretdgdh

tornadoes,powerful,destructive wind storms,occur most often in the spring when hot winds___over flat land encounter heavy,cold air.
为什么用rising不用 are rising？
Among the first plants to grow on the land region of Earth__,which in prehistoric times grew to immense size.
为什么用were horsetail rushes不选 horsetail rushes？哪个词表示要用倒装？
(Despite)television is the dominant entertainment medium for United States
households,Garrison's Saturday night (radio show )of folk songs and stories( is )hesrd by( millions )of peple.
despite应该怎么用呢？

himba

when引导的句子的谓语，are rising的are违背了主句专一原则

[em05]

teyvhf

只需要记住despite不能引导完整句子就可以了 相同的还有also,thereby,thus等，一下子就只记得这么多