He broke his right leg ______ he was playing football.A、sa B、while C、because D、since

问题描述:

He broke his right leg ______ he was playing football.A、sa B、while C、because D、since
He broke his right leg ______ he was playing football.
A、sa B、while C、because D、since
A是as

选B
while后面跟的是过去进行时,强调的是他在踢足球的同时,伤到了右腿.