What is an example of a sentence where there would be elision because of cacophony?
Elision is the normal omission of speech sounds and running words or syllables together to prevent cacophony. In normal unemphatic well-spoken English, the phrases two eyes and too wise are pronounced exactly the same, and likewise the phrases the ear and the year. The sentence "He asked his uncle if it was ok" would be spelled phonetically He yastiz zuncle lif fitwa zokay. Sadly, the poorest, most stitled speakers dominate, being heard all over the media separating their words and putting glottal stops before every syllable that begins with a vowel sound, so that we do hear people say "tha ocean" and "what:ever" instead of the correctly fluent "thee ocean" and "whaddever." "Cacophony" is harshness of speech sound. It results when speech is stilted, for example by putting a glottal stop before a syllable normally beginning with a vowel sound. What you seek, then, is an example in which speech sounds are omitted and the remaining sounds are run together so that the spoken word or phrase has a more pleasant sound. If we agreed that "This is Mrs. Zimmerman" sounded harsh to the ear because of the z-z-z repetition, then saying "thiz mizimmerman" would make the expression sound more pleasant because we lessened the repetition. Similarly, if we thought that "can of Coca Cola" sounded harsh because of the k-k, then saying "cana co-cola" would make the words sound more pleasant. [You may not agree that those changes are acceptable, but they are real-life examples that fit your question.] In the famous line by Alexander Pope, "When Ajax strives some rock's vast weight to throw," we might find that some people eliminate the harshness by "eliding" some of the sounds and saying, approximately, "When Ajak strive some rocks vass weigh to throw." In principle, elision, in the sense of omitting some speech sounds and running words together, is not always a fault and is, in fact, common in the speech of well-educated people who are skilled speakers of English. But that is a much longer story. A to B: "Would you like to sweep with me?"
B Hears: "Would you like to sleep with me?"
B to A: "That's very flattering, but no thank you. I have a boyfriend." Make the last line, B to A: "That's very flattering, but no thank you. I already have a groom." [We presume A heard "broom"]
A to B: "Great! Clean up the floor with it!"
B hears "him" instead of "it".