Diphthong
In phonetics, a diphthong is a vowel combination usually involving a quick but smooth movement from one vowel to another, often interpreted by listeners as a single vowel sound or phoneme.
While "pure" vowels are said to have one target tongue position, diphthongs have a moving tongue.
Pure vowels are represented in phonetic script by one symbol:
English "seem" as [si:m], for example.
Diphthongs are represented by two symbols, for example English "same" as [seim],
where the two vowel symbols are intended to represent approximately the beginning
and ending tongue positions.
Diphthongs in English: [5]
Diphthongs in Spanish:
Diphthongs in French:
Diphthongs in German: