外教课作业：设计一个生活中不存在的产品或发明，并用英语介绍，推销它，大概帮我想几个点子就行，谢谢！

我的感觉这个意思就是具体说一下他的功能和使用方法，一个物品的属性就是功用和外观。而且，臆想的东西，功能和结构可以完全没有关联。我认为这个作业的关键是：熟练应用有关介绍的英语句式，建议你找些有关介绍的英语文章就好了。

时光机吧，time travel，建议看看时间旅行者的妻子这部电影，提炼些语句。Time travel is the concept of moving between different points in time in a manner analogous to moving between different points in space.Time travel could hypothetically involve moving backward in time to a moment earlier than the starting point, or forward to the future of that point without the need for the traveler to experience the intervening period (at least not at the normal rate). Any technological device – whether fictional or hypothetical – that would be used to achieve time travel is commonly known as a time machine.