过去进行时was/were doing — 英语填空题
题目
Last night, Lily and her parents were watching the stars in the yard. While they ___ (sit) there quietly, a bright shooting star suddenly appeared. At that moment, her father ___ (take) photos of the sky and her mother ___ (not look) up, so only Lily saw it. 用所给动词的适当形式填空。