In the process of understanding: If she can speak English, why not? For any communication, you want to get your message across to your audience. In her speech, she pronuciated clearly, even though with some stutter - talk with continued involuntary repetition of sounds, especially initial consonants. I admire her courage to speak in non-native language, a way to show her sincerity to the world for a better life for women and children.
On top of everything else, sincerity is the most effective to convey your thought. As a top tier singer, she knows that well. Her training in singing serves well in speaking English.
You gotta listen to her speech to know what the heck I'm talking about, as below.
Chinese First Lady Peng Liyuan Delivers a Speech about Women and Education at UN GA 2015
It gives me a great pleasure to join you for this important initiative as the UN marks its 70th anniversary.
Education is very close in my heart. My father grew up in a very small village in China. In those days, not many villagers could read. So my father opened a night school to teach them how to read. With his help, many people learned to write their own names; with his help many people learned to read newspapers for the first time; with his help, many women were able to teach their children how to read.
As his daughter, I know what education means to the people, especially those without it. After generations of hard work, China has come a long way in education. I myself am a beneficiary of that progress. Otherwise I would never become a soprano and a professor of musical.
I am following my father’s footsteps by teaching at China’s Conservatory of Music to help continue China’s success story. I want to thank Director-General Bokova and UNESCO for naming me the Special Envoy for Women and Girls Education. I am truly honored to work with the UN and do something about Global Education. I have visited many schools around the world. I’ve seen first-hand on how much we can do for education.
Education is about women and the girls. It is important for girls to go to school because they will become their children’s first teacher someday. But women still account for over half of the world’s poor in population and 60% of adults who can’t read.
Education is crucial in the addressing such inequalities. In China, Spring Bud Education Program has helped over 3 million girls go back to school. Many of them have finished university education and they are doing well at work.
Education is about equality. In poor countries and regions the number of school dropouts is astonishing. We call for more educational resources to these places.
Education is about the young people. Young people are the future. Education is important because it not only gave young people knowledge and skills but also help them become responsible citizens. As the UNESCO special envoy and the mother myself my commitment to education for all will never change.
Many years ago my father made a small difference in his village. Together we can make a big difference in the world. I was once asked about my Chinese dream. I said I hope all children especially girls can have access to good education. This is my Chinese dream. I believe one day education first will no longer be a dream, it will be a reality enjoyed by every young woman on this planet.
(391 bytes) (42 reads) 09/28/2015 postreply 10:34:59 
别忘了她是中国首个声乐硕士
个人很喜欢彭，她讲英文很可爱！
比如常说我的洋朋友这样说，那样说，说明不单说英语好， 听力也非常好，要是老公是洋帅哥就更厉害了， 连叫床也用英语， 同胞不能比的。
另一方面，中国大陆人英语普遍不好，除了语言本身的差异以外，
说明我们的英语教育走进了一些弯路没出来。
一向认为英语和其它所有语言一样,工具,沟通的工具那是.
流利--大部分是指口语,有的时候涵盖演讲(即公开讲话),这里面的技巧实在是多.
社交性质的"交谈",这流利就表现出来了.让听的人感到轻松,容易领会,反应快捷,表达清晰,这些全部都是要点.
文化上的不自信,是大部分国人的病根.
第二，彭丽媛在联大说英语，与习近平在联大说中文，两者根本就不是一回事。习近平是国家元首，代表中国，他在联大说中文理所当然；而彭丽媛虽然是习近平夫人，基督教文化属于一，共产党文化属于二，但主要还是作为客人。中国客人造访美国，在人家国家说英语，乃是对东主国的尊重。
第三，美国人没有嘲笑别人英语发音和语法不正的习惯，不似咱们假正经的加拿大保皇党人，小布什总统的语法，大多数college和university里学生的写作水平，都不如移民。英国，德国，俄国，美国，大学者讲课，大官们辩论，从来说话都很慢，有时候就是一个单词一个单词地往外蹦。
别忘了，中国现如今不仅要秀钱包，还要精神输出，文化输出，因此中文要向全世界大声地讲，大声音地说！
就连英国财相近日为讨好中国都给他们的教育部发一大笔钱让他们的小学生普及中文教育，
我们的第一夫人为什么要在联大勉强秀英文呢？实在低估了国家（钱）的强大与自己的地位。
正如 “ linna118 ” 网友所说，我们喜爱彭丽媛，但美中不足是她身边有一个出 “馊主意” 的高参。
对彭丽媛是说英语对，还是说汉语对的问题，谁都有不同看法，无所谓谁对谁错，所以不该涉及对写此类博客的博主进行没有道理的攻击，什么时候人们都能就事论事而非上纲上线，人与人之间的关系就会平和很多。
赞这样因为有鲜明观点而有了议论价值的博客。
设想一下，要是在美国偶遇一位异国人士能说一些洋腔洋调的中文和你交流，你还会去挑毛病？只会觉得那个人很不错，会讲中文。语言是一个工具，不是拿来表演的。