A compound vowel is a vowel formed by combining two or three vowels. This compound vowel is not a simple addition of two vowels or three vowels. It is a new and fixed sound group, which has the same feeling with the unit rhyme in the mouth and ears, and should be regarded as a phonetic whole.
Extended data:
Pronounced complex vowel
Ai, ei, ao, ou 4. When pronouncing, the oral muscles are relaxed, and the rhymes A, O and E are pronounced clearly and loudly, and the sound value is slightly longer. The I and u(o) behind them are rhymes, which are light, short and vague, only indicating the direction of tongue sliding. Each vowel must be read as a whole. The endings I and u(o) are actually not in place, but loose vowels [I] and [U]. Such as:
Ai[ai]: Cabbage, Love, Rehearsal, Disaster, Terrace.
Ei[ei]: plump, equipped, bud, snitch, black coal.
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