Example 2: I cannot argue with those who find these men and women—some known, and some obscure to all but those they help to be far more deserving of this honor than I. (extracted from I Will Accept This Award as A Call To Action )

This is an example extracted from the speech on winning the Nobel Peace Prize. Many people argue that Obama does not deserve this prize. Facing all these doubt, Obama expressed his own attitude. He admitted that there are many people who deserve this Prize better than him. At the moment he accept the Award, he also carried the responsibility on his shoulder. The first person here shows directly his generosity toward controversy and responsibility as the president of the world’s strongest country.

Example 3: when I am president, I will sign a universal health care law by the end of my first term. My plan will cover the uninsured by letting people buy into the same kind of health care plan that members of Congress give themselves. (extracted from Turn the Page)

Above words were addressed to the members of Democratic Party to encourage them to work hard for the winning of the general election. In this example Obama directly described the future of his presidency. By this way, he made the whole party knew his idea so that they can work together for a same goal. Moreover, these words are Obama’s promise to the Party, which came from his heart. As a result, he earned the public’s trust for his honesty.

2.2 The Use of "We"
Speaking style varies with speakers. For example, Hilary Clinton，one of the presidential candidates of the Democratic Party, tends to say "when I am president" the most so she usually left the audience the impression of ambitious, strong and subjective. To John Edwards, another candidate, the most frequently used personal pronoun is "they". By using this word, he usually refers to hostile forces of American people or justice. When it comes to Obama, the personal pronoun of high frequency is "we". Generally speaking, "we" in his speeches refers to three kinds of groups. The first one is the whole American public. The second one is himself and the government represented by him. The last but not least is the audience and himself. By using "we", he created an intimate relationship between him and the audience. Moreover, this is also a method he used to unite the whole nation and call for cooperation on building a better America. Convincing examples can be found to prove this.

Example 4: We are choosing hope over fear. We’re choosing unity over pision, and sending a powerful message that change is coming to America. (extracted from Change Is Coming to America: Iowa Caucus Night)

As we all know, America is pride with its democracy. In example 4, the word "we" refers to the entire American citizen. By saying so, Obama implied that "choosing hope over fear" and "choosing unity over pision" is not only his idea but also the will of all the Americans. While taking democracy into consideration, He also tried to stroke up an alliance among the Americans so that they can work together for a same dream. From the point view of the Americans, after they heard Obama counting himself as one of them, they will feel closer to him and accept his opinion easier.

Example 5: The rescue plan that passed the Congress was a necessary first step to easing this credit crisis. And that’s important because we need make sure our business can still get loans. You can get loans eventually for college, for car mortgage, and all that stuff. But it’s also important that we continue to work with governments around the globe to confront now what is truly a global crisis. (extracted from Financial Crisis Requires Action)

The speech Financial Crisis Requires Action was made to fight against McCain’s economic plans. In this speech Obama explained his opinions eloquently and convinced even some of the Republic Party to support him. 浅谈奥巴马演讲中的语用策略(5):http://www.youerw.com/yingyu/lunwen_1567.html