毛毛是个10岁的孩子，说是孩子，其实在北京人当中算是中青年了，因为北京人生活环境恶劣，人们的寿命都不长。这天一大早，毛毛走出小木屋，他手里拿着一把铁制的镰刀去割水稻。时间过得真快，转眼已到正午，毛毛急忙往回赶，因为他还有一个重要的任务，就是要钻木取火，因为他要用陶锅做香喷喷的大米饭。

药品：①过氧化氢溶液   　②氯酸钾   　③二氧化锰

装置：

Hitchbot

    Have you ever seen a hitchhiker(搭便车的旅行者）standing by the side of a road? Now drivers in Canada might see____unusual hitchhiker; a hitchhiking robot.

    One of its inventors, David Harris Smith, has hitched across Canada three times. Smith and a friend, Frauke Zeller, have built Hitchbot because they wanted____(see) if people would stop and give the robot a lift and talk to it. The robot can chat about things it has learned, and about____(it) trip. You might think it's a joke,____Smith and Zeller's experiment has a serious point: can robots and people get along?

    Hitchbot____(begin) its journey in Nova Scotia in July. It has already completed a third of its 6,000-mile trip to Victoria. More than 57,000 people are following its journey____(close) on Facebook and Twitter, and travelers have posted lots of____(photo) on the websites. Hitchbot has also done some shopping, eaten motor oil, and had fun with travelers. Nobody knows____it will finish its journey. It might be____(long) than expected, but Zeller and Smith want Hitch to get____many rides as it can. It hasn't been in a self-driving car yet, but anything is possible!