Zunggàihàn'jýn (中介汉语)

Consonants
Allophony


 * [ʔ] occurs between consecutive vowels that aren't i, u or y, they become [j], [w] and [jy]
 * [w], [j] and [ʔ] are allomorphs of the null initial
 * t and k become [t̚] and [k̚~ʔ]
 * kj, khj and xj do occur, but they can be normally substituded by tɕ, tɕh and ɕ
 * tɕ, tɕh, ɲ and ɕ are always accompanied by the i or y medial (ɲ+ian>ɲan, tɕ+iou>tɕou, ɕ+jy>ɕy)

Latin
ʉ is normally replaced by i, since it only occurs in zʉ~zi, cʉ~ci and sʉ~si

ɵ can be put as ø or oe if not available and ʉ can be put as ue, although ʉ is practically never used

Tone is put via diachritics (平-入: a, 上: á, 去: à) and 阳 register is put with an h before the coda or uh or ih if u or i was the coda

If there's any ambiguity, an apostrophe is used.

Bopomofo
Tones are putted by a character after the syllable: 上: ˊ, 去:ˋ and the 阳 register:ˇ, so 阳上: ˇˊ,阳去: ˇˋ

You can use ˙ to separate syllables if it's needed.