Vowel modification refers to the changes in vowel sounds that occur in speech, often influenced by surrounding sounds or the phonetic context. This phenomenon can affect how vowels are pronounced, making them sound different from their standard forms. For example, in the presence of certain consonants, a vowel may become more nasalized or rounded. In linguistics, vowel modification is important for understanding dialects and accents. It can also play a role in language learning, as learners may need to adjust their pronunciation to match native speakers. This adjustment helps improve clarity and communication in languages like English or Spanish.