Unit 30. An Old Car, a Bottle of Water.

Important for listening!
When a word with a final consonant cluster ending /d/ is followed by another word beginning with a consonant sound, /d/ is often left out (see also Unit 9)
       An old car.     I changed clothes.    Can you find Mark?

Notice, however that -

• we don't usually leave out /d/ before vowel sounds or /h/
  Hand it over.    They served apple pie.      She seemed happy
  

• we don't usually leave out /d/ before the sounds /l/, /w/, /r/ and /s/
  Do you mind walking? (compare: Do you mind giving me a lift?) 

Note: When a word ending with /d/ is followed by a word beginning with /j/ (y), the /d/+ /j/ is usually pronounced /d3/ (as in 'June'). This happens both in consonant clusters and when the word ends with the single consonant sound /d/:
     Had you met before?    I'll lend you one. /<3з/
        /d3/                                     /d3/

Important for listening!
We often leave out /h/ at the beginning of the

• pronouns he, her, his, him
  I thought he was.     Did you meet her?    Ask him.

• the auxiliary verbs have, has, had
  The students have all left.     Karen had already left.

• the question word who
  Can you describe the person who did it?

However, /h/ is not left out if it is stressed or at the beginning of an utterance:
       It's not mine, it's his.    It's him!    Has Ken arrived?    Who did it?

Important for listening!
Before consonant sounds, and is usually pronounced /∂n/ or /n/ and of is pronounced /∂/:
      red and blue      now and then      a bottle of water      a waste of time

Before vowel sounds, and is usually pronounced /∂n/ or /n/ but of is pronounced /∂v/:
    pen and ink    Adam and Eve    a bag of apples    a can of oil