缅甸学生所发的二级元音都存在开口度偏大的问题，衔接得不自然，每个音都发得十足到位，多像是两个单元音的简单组合，而不像是个复元音。
Myanmar students ' level 2 vowel exist the bigger openness and convergence unnaturally , which are full of every sound , more like a simple combination of two vowels , not like a complex vowel .
复元音