英语语言学里面"diphthong"的定义是什么?
遇到这样一个问题,有个试卷里面其中有一题要我们用英语 define,"what is diphthong"?找过很多网站都没有想要的答案，请高手指点一下。
diphthong /df, dp-/ (diphthongs) N-COUNT A diphthong is a vowel in which the speaker's tongue changes position while it is being pronounced, so that the vowel sounds like a combination of two other vowels. The vowel sound in `tail' is a diphthong. 就是音标里的双元音
比较好的词语定义网站，里面有两种辞典的定义和同反义词。下面复制的定义： Meaning of DIPHTHONG Pronunciation: 'difthong WordNet Dictionary Definition: [n] a vowel sound that starts near the articulatory position for one vowel and moves toward the position for another Webster's 1913 Dictionary Definition: 1。
\Diph"thong\ (?; 115, 277), n。 [L。 diphthongus, Gr。 ?;di- = di`s- twice + ? voice, sound, fr。 ? to utter a sound:cf。 F。 diphthongue。
] (Ortho["e]py) (a) A coalition or union of two vowel sounds pronounced in one syllable; as, ou in out, oi in noise; -- called a {proper diphthong}。
(b) A vowel digraph; a union of two vowels in the same syllable, only one of them being sounded; as, ai in rain, eo in people; -- called an {improper diphthong}。
2。\Diph"thong\, v。 t。 To form or pronounce as a diphthong; diphthongize。 [R。] 。
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