Ok, see this video: https://www.youtube.com/watch?v=hq3yfQnllfQ
At 0.:16
, you will hear "A for apple" /eɪ fɔː ˈræp.l̩/
--> clearly the speaker linked /r/
& /æ/
.
At 0.:18
, you will hear "A for ant" /eɪ fɔːr ænt/
--> clearly the speaker did not link /r/
& /æ/
.
At 0.:18
, you will hear "E for egg" /iː fɔːr eɡ/
& "E for elephant" /ˈel.ɪ.fənt/
--> clearly the speaker did not link /r/
& /e/
.
SO, why sometimes we do link the last consonant of before word & the first vowel of after word & sometimes we don't?
Or is that because the English ability of the Kid in the video (even though she is a native) has some limits & that is why she didn't know how to link?