Diphthong is a vowel sound in which the tongue changes position to produce the sound of two vowels

Diphthongs
What is diphthong?

"Diphthong is a vowel sound in which the tongue changes position to produce the sound of two vowels"

(Cambridge Advanced Learner's Dictionary)
Diphthong is a single sound produced when two vowels (one dominant in duration and stress, and one reduced in duration and stress), are paired together in sequence".
There are 8 diphthongs in English:
[eɪ] take /teɪk/

[aɪ] side /saɪd/

[əʊ] hope /həʊp/

[ɔɪ] boy /bɔɪ/

[ɪə] here /hɪər/

[eə] hair /heər/

[ʊə] boor /bʊər/

[aʊ] now /naʊ/

Examples:





[aɪ]

The /a/ is longer in duration and forms the nucleus of the diphthong, while /ɪ/ is shorter and unstressed.

Here are some words that start with the /aɪ/ sound.

• 
  idea /ˈaɪðә/
  
• 
  either /ˈaɪðә/
  
• 
  item /ˈaɪtәm/
  

Here are some words with the /aɪ/ sound in the middle.

• 
  child /tʆaɪld/
  
• 
  while /waɪl/
  
• 
  might /maɪt/
  
• 
  five /faɪv/
  

Here are some words with the /aɪ/ sound at the end.

• 
  try /traɪ/
  
• 
  high /haɪ/
  
• 
  why /waɪ/
  
• 
  guy /gaɪ/