为一段缺少标点符号和大写字母的长句添加适当的标点符号和大写字母。
i have a dream that one day this nation will rise up and live out the true meaning of its creed we hold these truths to be self-evident that all men are created equal.
I have a dream that one day this nation will rise up and live out the true meaning of its creed. We hold these truths to be self-evident that all men are created equal.