To find out what the exact rhyme is, you need to understand what the phonemes are. Phonemes are the sounds produced by the speakers and represent the sound units that form the words of a language. Human beings produce sounds that articulate, join together, and form words.
The exact rhyme is that which is formed by the coincidence of phonemes, that is, not only formed parts terminations vowel of lines (as we usually see), but is formed by the consonants that precedes the stressed syllable, and in its interior.
