Now, coumarin is a very common thing, a material, in fragrance which is derived from a bean that comes from South America. 香豆素是香水中一个十分平常的原料，从来自南美的豆子中提炼出来的。 And it is the classic synthetic aroma chemic

President Faust, members of the Harvard Corporation and the Board of Overseers, members of the faculty, proud parents, and, above all, graduates: 尊敬的福斯特校长，哈佛集团的各位成员，监督理事会的各位理事，各位老师，各位自豪的家长，尤其是毕业生们： Th

Five years ago, I experienced a bit of what it must have been like to be Alice in Wonderland. 五年前，我曾有过一个有如漫游爱丽丝仙境的经历。 Penn State asked me, a communications teacher, to teach a communications class for

李克强总理 应印度共和国总理辛格邀请，国务院总理李克强于2013年5月19-5月22日对印度进行正式访问。5月21日，李克强总理在新德里应印度世界事务委员会之邀发表的题为《把握中印战略合作新机遇》的演讲，获得强烈反响。 把握中印战略合作新机遇 Seize the New Opportunities in China-India Strategic Cooperation ——在印度世界事务委员会的

Life doesn't always present you with the perfect opportunity at the perfect time 生活不会总在完美时间将完美机遇放到你的面前 Opportunities come when you least expect them 机遇经常出现在你最不指望它们出现的时候 or when you're not read