Linking R sound in English pronunciation

How to use the Linking R sound in English pronunciation 

The Linking R sound in English is an extra sound that we use between two words when we are connecting these two words together. If we pronounce the two words separately, we do not use an R sound between them but if we pronounce them together, we say an R sound between the words because it makes the words easier to pronounce quickly.

https://www.dailystep.com/en/blog/linking-r-sound-english-pronunciation Listen to these pairs of words. The first time, I will say them separately, and the second time I will pronounce them together:

Four apples - four apples - Here and now - Here and now

We use a linking R sound when the first word ends with one of these simple vowel sounds: /ɑ:/, /ɔ:/, /ɜ:/, /ə/, or with any of these diphthongs (double sounds): /eə/, ɪə/ and /ʊə/, and the second word begins with a vowel sound. 

In the examples below, you can hear that there is no linking R sound where each underlined word starts with a consonant sound. But where each underlined word starts with a vowel sound, we add a linking R so that the words can be said more quickly and easily.

End sound of first word	Examples	No linking R sound	Linking R sound
ɑ:	car spa	The car was mine. The spa was closed.	The car R is mine. The spa R is open.
ɔ:	door saw	The door was blue. I saw two cats.	The door R is open. I saw R a cat.
ɜ:	were her	There were three dogs. Her coat is black.	There were R eight dogs. Her R eyes are brown.
ə	brother future	My brother lives there. The future will come.	My brother R is younger. The future R is bright.
eə	hair wear	His hair was dark. I wear this coat.	His hair R is dark. I wear R it to work.
ɪə	year steer	A year lasts for 12 months. Steer the car this way.	A year R is 12 months long. Steer R it with a wheel.
ʊə	pure cure	Pure gold is valuable Can we cure cancer?	Is this gold pure R or not? Can we cure R it?

Now, try saying the sentences that have the Linking R sound quickly, but without using the Linking R. I will try some now, first without using the Linking R – and you will hear that they sound quite unnatural – and then using the linking R correctly.
The car is mine -    the car is mine

I saw a cat -   I saw a cat

His hair is dark -   His hair is dar
Sometimes the Linking R sound can confuse English learners. Listen to these pairs of words – they sound the same!

Her eyes   -    Her rise

Their age  -    Their rage

Her ace     -    Her race

So it is very important to be aware of the Linking R sounds because otherwise you can hear the wrong words! (by Jane Lawson at DailyStep.com)