I___in this room watching television when someone on the door.
A. sat… knocked
B. sat … was knocking
C. was sitting … knocked
出自:国家开放大学-人文英语3

完成拼图验证

按住下方滑块,将拼图拖到缺口处后松开。

拼图背景,将小拼图拖到缺口处
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