1. Rhetorical Devices Used by Speakers and Writers
Rhetorical devices are the nuts and bolts of speech and writing; the parts that make a communication work. Separately, each part of is meaningless, but once put together they create a powerful effect on the listener/reader.

2. Alliteration
It creates a musical effect in the text that enhances the pleasure of reading a literary piece. It makes reading appealing. Furthermore, it renders flow and beauty to a piece of writing.
Consider the following examples:
But a better butter makes a batter better.
A big bully beats a baby boy.

3. Parallelism
Writing structures that are grammatically parallel helps the reader understand the points better because they flow more smoothly.
If there is anyone out there who still doubts…who still wonders…who still questions

4. Emotional Language
Emotive Language. Writers use emotive language in order to have a greater emotional impact on their audience.
Words can evoke positive emotions, as in: 'Brave grandma risks life to save sick orphan'.
Or the goal can be more negative: 'Abandoned children found in filthy, flea-infested flat‘.

5. Repetition
Repetition can be effective in creating a sense of structure and power. In both speech and literature, repeating small phrases can ingrain an idea in the minds of the audience.
Yes, we can, to opportunity and prosperity. Yes, we can heal this nation. Yes, we can repair this world. Yes, we can.

6. Figurative speech
People like to think in metaphors. The image of bending the arc of history up towards hope is powerful. Figurative speech tends to work best when set off by concrete images.
“the arc of history with the backyards of Des Moines and the living rooms of Concord and the front porches of Charleston”

7. Rhetorical Question
A question which is posed without the expectation of an answer is called a “rhetorical question.”
Dropping a rhetorical question into a persuasive argument is often a powerful form of persuasion. You present several facts and build up to a conclusion, drawing the conclusion out of the reader. 

8. Varied Sentence Length
Varying the sentence length is always a good way to strengthen any writing style, be it speech writing or essays.
--“To the best campaign team ever assembles in the history of politics: you made this happen, and I am forever grateful for what you’ve sacrificed to get it done. But above all, I will never forget who this victory truly belongs to. It belongs to you. It belongs to you.”

9. Rhetorical & Persuasive Appeals
Ethos—appeal to ethics; asks the reader/listener to look favorably on the writer/speaker; stresses the writer/speaker’s intelligence, competence, fairness, morality, and other qualities desirable in a trustworthy leader.
--“I promise you, we as a people will get there.”
--“But I will always be honest with you about the challenges we face. I will listen to you, especially when we disagree. And, above all, I will ask you to join in the work of remaking this nation . . .”

10. Rhetorical & Persuasive Appeals
Logos—rational appeal; asks the readers to use their intellects and powers of reasoning. It relies on established conventions of logic and evidence.
--Can you find any use of logos in this speech?

11. Rhetorical & Persuasive Appeals
Pathos—an emotional appeal; asks readers to respond out of their beliefs, values, or feelings. It inspires, affirms, frightens, angers.
--“Tonight we proved one more that the true strength of our nation comes not from the might of our arms or the scale of our wealth, but from the enduring power of our ideals: democracy, liberty, opportunity, and unyielding hope.”
--“Yes we can.”
--“So tonight, let us ask ourselves—if our children should live to see the next century; if my daughters should be so lucky to live as long as Ann Nixon Cooper, what changes will they see? What progress will we have made?”