3. • Like i, when the initial vowel u is followed by the main vowel,
u is a transitional sound.
uā uá uǎ uà
• If there are vowels or nasal consonants after the main vowels,
they should be unstressed as well.
uāi uái uǎi uài
14. • In üe, e is main vowel, ü is a transitional sound which is not
stressed.
• If there is no initial consonant before üe, add a y and drop the
umlaut. thus üe becomes yue.