介绍奥巴马的英语作文
Obama was elected as the new president of the USA. He was popular among American people not only because he is black but is also because he is quite young and a very powerful lawyer before this.
He is the son of a black man from Kenya Africa and a white woman from America.He used to be a lawyer in Chicago for several years.
He will come to office in early January.
奥巴马是平民出身所以美国有的总统是平民分析省略的三段论
大前提：奥巴马是平民出身，
小前提：奥巴马是美国总统，
结论：有的美国总统是平民出身。
这个省略三段论省略了小前提，恢复后，是个有效的三段论形式。
10分钟左右演讲 PPT多少页合适?
要看内容，一分钟能讲一页的内容，就要10页，十分钟只能讲一页的，只需一页，一分钟可以讲10页，就要100页。