Oil and coal come from the plants and animals that died___of years ago

题目

Oil and coal come from the plants and animals that died___of years ago
A.billion B.millions C.thousand D.many hundreds

答案

B数词不能用形容词再修饰,不过可以加S表不确定数字.如hundred of,数以百计的,thousands of数以千计的,millions of数以百万计的.