English Diphthongs
Diphthongs are sounds formed by combining two vowels in a single syllable. The sound starts as one vowel and moves toward another, creating a slide or glide.
About English Diphthongs
English has several diphthongs, which are sometimes challenging for language learners because they require a smooth transition from one vowel position to another. Rather than two separate vowel sounds, a diphthong is a single sound unit in which the tongue moves from one position to another.
Some linguists categorize "long vowels" in English as diphthongs because they often involve a slight change in position during pronunciation.