问答题 "How to open the door?" , he asked as he turned the key, but the door did not open.
【正确答案】正确答案：turned—was turning
【答案解析】解析：句意：“这门怎么开啊?”他一边转动钥匙，一边问，但是门就是打不开。此句是一个用as连接的时间状语从句，根据上下文应用过去进行时态。