当时他正被车撞倒是不是翻译为When he was being knocked down by the car

题目

当时他正被车撞倒是不是翻译为When he was being knocked down by the car

答案

He was being knocked down by the car at that moment.
才是一个完整的句子吧,when开头是用在从句中的.
你是要怎么用呢?