This sound is /r/, as in the word 'risk.'

This sound is /r/, as in the word 'risk.' Avoid adding a vowel sound at the end. It’s not /ruh/, but /r/. And with this sound we also have to avoid adding a vowel sound at the beginning. It’s not /errr/ but /rrr/. The International Phonetic Alphabet (IPA) represents this phoneme with the following symbol: r. In the early stages of the curriculum, Once’s instructional content represents the sound with a symbol that is made by typing ‘r’ in a specialized font. This specialized orthography helps beginning readers (pre-kindergarten students through early elementary grades) learn letter-sound correspondence more quickly. By the middle stages of the curriculum, the specialized orthography is phased out and replaced by letters in a serif font.