53. (2018兰州)My sister with my parents ________ dumplings when I got home yesterday evening.
A. are making  B. is making  
C. was making  D. were making
53. C【解析】考查过去进行时。句意：当我昨天晚上到家的时候，我的妹妹(姐姐)和我的父母正在包饺子。根据yesterday evening可知，是昨天晚上正在做的事情，用过去进行时。故选C。