Prosody is not just a tune--it is a percussion
This feature of prosody is one of the hardest things to acquire in a new language. Yet the baby is demonstrating a knowledge of it as early as six months!
Prosody is made up of a number of elements that include rhythm, inflection, stress and juncture.
The rhythm of a language involves the combinations of vowels and consonants and the treatment of the vowels. It creates a cadence that we come to expect of a language. It is what poems are made of, and poems are a good way for foreign students to practice the rhythm of the new language.
This rhythm is very important for effective listening as far as speech is concerned, because it helps to break the stream of sounds into their proper units.
When we impose the wrong rhythm on a language, we are segmenting the stream of speech incorrectly and it becomes much more difficult to decode. Notice, that when foreign speakers speak English using their native rhythm, English becomes very difficult to understand.