English Sounds Chart (Vowels and Diphthongs):

Vowels and Diphthongs

Phonetic Symbol	Key Words
/ / as in	"sit"	"kick"	"grid"
/ ε / as in	"pen"	"bed"	"peck"
/ æ / as in	"hat"	"mass"	"can"
/ a / as in	"pot"	"bought"	"sock"
/ ʊ / as in	"put"	"foot"	"book"
/ ʌ / as in	"but"	"truck"	"mud"
/ ə / as in	"about"	"machine"	"offend"
/ iy / as in	"see"	"flea"	"beet"
/ ey / as in	"say"	"cake"	"bale"
/ uw / as in	"too"	"clue"	"shoe"
/ ow / as in	"go"	"sow"	"boat"
/ ay / as in	"buy"	"fight"	"mine"
/ aw / as in	"now"	"plough"	"sow"
/ oy / as in	"coin"	"boy"	"noise"
/ ir / as in	"fear"	"steer"	"beer"
/ er / as in	"bear"	"hair"	"stare"
/ ur / as in	"boor"	"poor"	"sure"
/ or / as in	"bore"	"score"	"floor"
/ ər / as in	"her"	"fir"	"were"

A diphthong is a speech sound considered as one distinctive vowel of English, but really involves two vowels, with one vowel “gliding” to the other. This means that as the mouth is forming the first vowel sound, the tongue smoothly moves into the position to make the second vowel sound.

The slanted brackets are meant to remind us that we are talking of sounds, not letters.