Coalescence (or fusion)

Coalescence (also known as fusion) is a sound change in which two or more segments with distinct features merge into one.

The alveolar consonants /t/ /d/ /s/ and /z/ may coalesce with a following /j/ (voiced palatal semi-vocalic) to form /ʧ/, /ʤ/, /ʃ/, or /ʒ/

/t/ followed by /j/ = /ʧ/

• want your / wɒnʧə / I want your money.
  
  
• want you / wɒnʧʊ / They want you back. /
  
  
• what you want / wɒʧʊ wɒnt / I know what you want.
  
  
• get you / geʧʊ / I'll get you a diamond ring.
  
  
• can't you / kɑ:nʧʊ / Can't you come back.
  
  
• that you're / ðəʧɔ: / I know that you're my friend.
  
  
• don't you / dəʊnʧʊ / Don't you dare do that.

/d/ followed by /j/ = /ʤ/

• Could you / kʊʤʊ / Could you keep the noise down?
  
  
• Would you / wʊʤʊ / Would you mind if I leave?
  
  
• Did you / dɪʤʊ / Did you see that film?
  
  
• Had you /hæʤʊ / Had you arrived earlier as I told you / təʊlʤʊ / to do, you wouldn't have missed lunch.
  
  
• find you / faɪnʤʊ / I don't know where to find you.
  
  

/s/ followed by /j/ = /ʃ/

• in case you / ɪŋ keɪʃʊ / Look out in case you fall
  
  
• of course you did / əv kɔ:ʃʊ dɪd /
  
  

/z/ followed by /j/ = /ʒ/

• as you wish / əʒʊ wɪʃ /
  
  
• Has your visitor left? / hæʒɔ: vɪzɪtə left /