Antonyms, Rhyme, Alliteration
Professional speechwriters like to deploy words and phrases that play off one another to make them delightful to the ear and memorable.
Antonyms
Antonyms are words that are opposites of each other and provide contrast, like day and night, slow and fast, teacher and student, hot and cold.
Winston Churchill was fond of antonyms, as cited in James Humes's Speak Like Churchill, Stand Like Lincoln:
“There is only one answer to defeat and that is victory.”
“This is not the end, nay, not even the beginning of the end, but it is, perhaps, the end of the beginning.”
“If the present quarrels with the past, surely the future will already have been lost.”
Benjamin Franklin also used them in many of his sayings (“never leave that for tomorrow which you can do today”).
Rhyme
Among the examples of internal rhyme that Churchill used:
“Out of intense complexities, intense simplicities emerge. Humanity, not legality, should be our guide.”
“Those professional intellectuals who revel in decimals and polysyllables …”
Likewise, Franklin incorporated rhymes in many of his maxims:
“Early to bed, early to rise, makes a man healthy, wealthy, and wise.”
“An apple a day keeps the doctor away.”
Muhammad Ali built his career around using rhyme to create memorable sound bites. Ali once explained his ring strategy as, “I outwit them and then I out-hit them.” Some have speculated that his style helped launch rap music, since its power rests largely on the rhymes of the spoken word.
Humes says that speechwriters often turn to nine word-endings “for coining ‘zinger’ lines”: ame (blame, claim), air (bear, care), ite (bite, cite), ake (ache, break), ow (dough, flow), ay (day, pray), ate (date, fate), eem (beam, cream), ain (gain, pain).
Alliteration
In alliteration, the same consonant sound repeats consecutively, as in “Peter Piper picked a peck of pickled peppers.” Less heavy-handed use is common in advertising: Holiday Inn's “pleasing people the world over” and Land Rover's “the best four-by-four by far.”
It can convey a sense of lightheartedness. You can use it for the title of a talk: “God Grants Goodness” or “Alleviating Arthritis Alternatively.” Again, the goal is to make a phrase memorable and entertaining.

