A blend vowel is a sound composed of two or more vowels, such as “ai” (a +i ), where the accent is on “a, “which should pronounce clearly and correctly as a single vowel, but the second part should pronounce short and quick.
The tone mark is not always at the first part, depending on single vowels, and generally, the tone mark follows a>o>e>i>u; that means
“A “always is accented like in iang, iao; the accent of “ue” is on “e, “and the stress of “iong “is on o.
1. ai an ang ao
2. ei en eng er
3. ia(ya) ian(yan) iang(yang) iao(yao) ie(ye) in(yin) ing(ying)
4. ong ou
5. ua(wa) uai(wai) uan(wan) uang(wang) ue ueng(weng) ui (wei)
6. üan(yuan) ün(yun)