ZS1BK_AF2B Fonetika a fonologie 2B - AJ
DIPHTONGS
diphthong noun [C] specialized
a vowel sound in which the tongue changes position to produce the sound of two vowels
(Cambridge Advanced Dictionary)
practice your diphtongs using the web link below:
http://www.oup.com/elt/global/products/englishfile/elementary/c_pronunciation/pronunciation02/