【答案】An apple ______ from the tree and hit on Newton’s head many years ago . He felt strange and appeared

An apple ______ from the tree and hit on Newton’s head many years ago . He felt strange and appeared “Newton physical gravity” .

A. is falling B. falls C. fell D. falling

【答案】

C

【解析】

句意“许多年前，一个苹果落下打在牛顿头上，他感到很奇怪，并发现了牛顿万有引力”。根据many years ago可知，用过去时，故选C。