完成对话 A: I thought you were working until 6:30.   B: ___________, but we finished our meeting at 5:30 and were let go.
【正确答案】 B
【答案解析】A说:“我想你应该工作到6:30。”B回答:“应该是,但会议5:30就结束,然后就可以走了。”选择B最合适,be supposed to意思是“应该是”。