Long vowel / :/ (Nguyên âm dài / :/) .Unit 11 Long vowel / :/ Nguyên âm dài / :/ Introduction / / is a long vowel sound. Your mouth and tongue should be relaxed. It’s pronounced / bird /b turn /t first /f work /w verb /v rd/ rn/ rst/ rk/ rb/ / / /. occur /ə k early / thirty / θ journey / d worship / w r rli/ rti/ rni/ p/ r/ .curtain / k The girl saw the circus first. /ə rl s .ə s rkəs .