听力原文
I am happy to join with you today in what will go down in history as the greatest demonstration for freedom in the history of our nation.

Five score years ago, a great American, in whose symbolic shadow we stand today, signed the Emancipation Proclamation. This momentous decree came as a great beacon light of hope to millions of Negro slaves who had been seared in the flames of withering injustice. It came as a joyous daybreak to end the long night of their captivity.

But one hundred years later, the Negro still is not free. One hundred years later, the life of the Negro is still sadly crippled by the manacles of segregation and the chains of discrimination. One hundred years later, the Negro lives on a lonely island of poverty in the midst of a vast ocean of material prosperity. One hundred years later, the Negro is still languished in the corners of American society and finds himself an exile in his own land. And so we've come here today to dramatize a shameful condition.

In a sense we've come to our nation's capital to cash a check. When the architects of our republic wrote the magnificent words of the Constitution and the Declaration of Independence, they were signing a promissory note to which every American was to fall heir. This note was a promise that all men, yes, black men as well as white men, would be guaranteed the "unalienable Rights" of "Life, Liberty and the pursuit of Happiness." It is obvious today that America has defaulted on this promissory note, insofar as her citizens of color are concerned. Instead of honoring this sacred obligation, America has given the Negro people a bad check, a check which has come back marked "insufficient funds."
参考译文
今天，我高兴地同大家一起，参加这次将成为我国历史上为了争取自由而举行的最伟大的示威集会。

100年前，一位伟大的美国人签署了《解放宣言》，而今天我们就站在他象征性的身影下。这项重要法令的颁布，对于千百万受于非正义压迫中的黑奴，犹如带来希望之光的硕大灯塔，好像结束漫漫长夜禁锢的欢畅黎明到来。 然而，100年后，黑人依然没有获得自由。100年后，黑人依然悲惨地蹒跚于种族隔离和种族歧视的枷锁之下。100年后，黑人依然生活在物质繁荣的贫困孤岛上。100年后，黑人依然在美国社会中间向隅而泣，依然感到自己在国土家园中流离漂泊。所以，我们今天来到这里，要把这骇人听闻的情况公诸于众。

从某种意义上说，我们来到国家的首都是为了兑现一张支票。我们共和国的缔造者在拟写宪法和独立宣言的辉煌篇章时，就签署了一张每一个美国人都能继承的期票。这张期票向所有人承诺—不论白人还是黑人—都享有不可让渡的生存权、自由权和追求幸福权。然而，今天美国显然对她的有色公民拖欠着这张期票。美国没有承兑这笔神圣的债务，而是开始给黑人一张空头支票—张盖着“资金不足”的印戳被退回的支票。
词语解释
1. symbolic n. 象征的,象征性的

The gestures are highly stylized and symbolic.
各种姿势都是高度程式化的，并且具有高度象征意义。

2. Proclamation n. 宣布,公布

The President issued an official proclamation of neutrality on September 5,1939.
总统于1939年9月5日发布正式中立声明。

3. Negro n. 黑人

He was the most amazing specimen of the southern Negro I had ever met.
他是我所遇到的南部黑人中最令人惊异的怪人。

4. dramatize v. 戏剧性地描述;生动地表达

The film attempts neither to dramatize nor sermonize.
这部电影既不企图使用戏剧化的手法也不企图进行说教。