R Practice Sheets:
r-initial words (mommyspeechtherapy.com)
Microsoft Word - initial r words consonant r.doc (heatherspeechtherapy.com)
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Videos Teaching R Production:
R sounds - YouTube
CORRECT PRONUNCIATION OF LETTER R IN NATIVE ENGLISH PART 1 - YouTube
(1) How to Pronounce the R and L sounds - YouTube
(1) how to say R perfectly in English | American English Pronunciation Lesson - YouTube
Learn the American accent! How to Pronounce the ER /ɝ,ɚ/ Vowel - YouTube