- Rhotic & non-rhotic accents: A rhotic accent is one in which the R is pronounced in all contexts (i.e. beginning, middle and end of a word). General American English is rhotic. Non-rhotic accent, by contrast, is one in which the R is only pronounced when it precedes a vowel. Standard Southern British English is non-rhotic.
- Hiatus: It's the separation of the sounds of two consecutive vowels that occur in adjacent syllables. For example, pronounce idea of as [aɪdɪə_əv] without an intrusive consonant.
- Connected speech: Connected speech is spoken language in a continuous sequence i.e. a continuous stream of sounds without clear-cut borderlines between words.
In connected speech, we try to link the vowels and consonants in order to provide a hiatus. When a word ends with one vowel and the next word starts with another vowel, it can result in a hiatus, so we put an epenthetic consonants in order to join those words. There are three main types of linking consonants:
1. Intrusive /j/: When one words ends in /i/, /aɪ/, /ɔɪ/, /eɪ/, and the next word begins with a vowel, there's often a glide /j/ between them. For instance, he is is pronounced [hiːjɪz] rather than [hiː ɪz] in connected speech.
2. Intrusive /w/: When one word ends in /u/, /aʊ/, /əʊ/ etc., and the next word begins with a vowel, English speakers are likely to insert an intensive /w/, as in go away, pronounced [ɡəʊwəweɪ].
3. Intrusive /r/: When one word ends in /ə/, /ɔː/, /ɑː/, /ɪə/ etc., and the next word begins with a vowel, most non-rhotic speakers will insert an epenthetic /r/ as in:
- idea of → [aɪˈdɪəɹəv] (idea/r/of)
- idea about → [aɪˈdɪəɹəbaʊt] (idea/r/about)
- saw a film → [sɔːɹəfɪɫm] (saw/r/a film)
- law and order → [lɔːɹənɔːdə] (law/r/and order)
'Intrusive /r/' is increasingly common in British English. You'll also hear it after proper nouns, for instance, Obama/r/administration, Stella/r/and stellar etc.
Note, however, that when there's an R in the spelling as in far away, the /r/ is called 'linking /r/', when there isn't, it's called 'intrusive /r/'.
/j/ is the 'y' in you, /w/ is the 'w' in wine, [ɹ] is the English R sound as in ring