What type of vowels are characterized by the controlling influence of a following consonant?

The type of vowels that are characterized by the controlling influence of a following consonant is known as R-controlled vowels. These vowels occur when a vowel is followed by the letter 'r', which alters the sound of the vowel, often making it difficult to hear its original sound. For example, in words like "car," "her," and "bird," the 'r' changes how we pronounce the preceding vowel, creating a unique sound that is distinctly different from both long and short vowels, which are not influenced by a consonant in such a way.

In contrast, long vowels are those that say their name (like the 'a' in "cake"), and short vowels have a more muted sound (like the 'a' in "cat"). Diphthong vowels consist of a complex vowel sound that begins with one vowel sound and glides into another within the same syllable, such as in the word "coin." R-controlled vowels stand apart in their specific interaction with the 'r' that follows them, making them a distinct category of vowel sounds.