And so even though we face the difficulties of today and tomorrow, I still have a dream. It is a dream deeply rooted in the American dream. 

即兴演讲，on the spot/improvise/make it up as you go along开始动之以情

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."

self-evident/crystal clear /clear cut不言而喻

nip it in the bud

live out: 宾语太长，将宾语后置

I have a dream that one day on the red hills of Georgia,  the sons of former slaves and sons of former owners will be able to sit down together at the table of brotherhood. 

one/son

重复: former slaves and sons of former owners.

有重复和有变化才是好的写作

I have a dream that one  day even the state of Mississippi, a state sweltering with the heat of injustice, sweltering with the heat of oppression, will be transformed into an oasis of freedom and justice. 

背诵：

I have a dream that my four little children will one day live in a nation where they will not be judged  by the color of their skin but  by the content of their character. 

I have a dream today. 

感情牌

Get something out of your chest.