用方框中所给单词的适当形式填空,使短文完整,通顺theypeaceresearchpollutebillionprovideawfulcleanreasonawayhowwastheearthofyearsagotheworldwasmuchwarmerthanitisnow.therewasn'tanywinterorsnow.thes

Question

用方框中所给单词的适当形式填空,使短文完整,通顺
they peace research pollute billion provide awful clean reason away
how was the earth ___ of years ago the world was much warmer than it is now .there wasn't any winter or snow .the sky ___ warm rain for the living things .even the sea was warm .in this warm world lived some strange animals called dinosaurs .they had been the kings of the world for a long time .
in the days of the dinosaurs ,there were no men .that is the ___ that no man has ever seen a living dinosaur .they lived in ___ in nature .after many years of ___ ,we found out some information about ___ .
some dinosaurs lived not far ___ from the water while others lived on dry land .most dinosaurs ate plants .many dinosaurs were very large ,but some of them were as small as chickens .
millions of year later .something ___ happened to dinosaurs .they began to die out .was the food they ate ___ or did they not have ___ water to drink no one knows the answer .

Answer 1

billions
provided
reason
peace
research
them
away
awful
polluted
clean