They saw a Bejing opera (last week)对框出来的部分提问：____ ____ they ____ a Beijing opera?
问题描述：
They saw a Bejing opera (last week)
对框出来的部分提问：____ ____ they ____ a Beijing opera?
答
when did see 希望采纳！谢谢！
答
对时间进行提问
应为“When did they see a Beijing opera?”
答
(When did ) they ( see ) a Beijing Opera
分析：问时间用WHEN,实义动词作谓语,一般过去时要加助动词DID,原来的动词要用原形,即saw -> see.
加油!不明白再问!
答
When did see