在铁路道口遇到两个红灯交替闪烁时要停车等待。
参考答案：对
—A new book on how to lose weight is _________ soon.
—Really? I can't wait to read it. [ ]
A. giving out
B. coming out
C. working out
D. selling out
烟卷中含有大量的有害物质---烟碱，烟碱也称（）。
A、一氧化碳
B、尼古丁
C、微尘
