Learn yod coalescence: /t/ + /j/ and /d/ + /j/ often merge to /tʃ/ and /dʒ/ in fast speech.
/t/ + /j/ may become /tʃ/ (e.g., don't you → /dəʊntʃu/). /d/ + /j/ may become /dʒ/ (did you → /dɪdʒu/).
Do not force it in careful speech; the careful form is also correct.
Do you have a /t/ or /d/ sound immediately before a /j/ (y) sound? If yes, coalescence may happen.
💡 This is common in fast, informal speech. British vs US note: yod coalescence exists in both varieties, but /j/ (the 'yod') itself varies: many US speakers drop /j/ in words like 'tune' (toon), which can change where coalescence occurs.
✓did you → /dɪdʒu/ (common)
✗did you → /dɪd juː/ (always separated)
The /d/ and /j/ can merge into /dʒ/.
✓would you → /wʊdʒu/
A very common reduction in questions and offers.
✓don't you → /dəʊntʃu/
The /t/ + /j/ combination can become /tʃ/.