What is the initial vowel in pinyin?

overall syllables: zhi chi Shi Li zi ci si yi Wu Yu yin ying yi yue yuan * * * 16.

single vowel: a o e i u u (fish)

compound vowel: ai ei ui ao ou iu ie ue er an en yin un (dot on u) ang eng ng ong.

initials: b p m f d t n l g k h j q x z c s zhi chi Shi ri y w.

tonal songs: one syllable and one tone, with tone symbols like a top hat.

Where should key signature be marked? Only mark it at the beginning of the vowel.

When you see a, a is marked, but there is no A, look for O, E,

I and U, and don't mark them softly.

there is one more thing to remember, and the marked points should be removed.

As for sound insulation, it is to prevent the last letter of the previous syllable from being mistaken for the initial of the next syllable.

for example, "conviction" (fɑn'ɑn) will be pronounced as "challenging" (fɑnɑn).