Minangkabau Debuccalization

 I just found out that there's a pattern to the debuccalization in Minangkabau:

• p > uk
• t > ik
• k > ak
• s > ih
• h > ah
• r > a
• l > -
• ng > ang

And then, there's monophthongization:

• ai > e
• au > o

So putting them together, you get this pattern from Indonesian to Minangkabau:

• kipas > kipaih > kipeh
• panas > panaih > paneh
• asap > asauk > asok
• acap > acauk > acok
• rapat > rapaik > rapek
• sikat > sikaik > sikek
• busuk > busuak
• tunjuk > tunjuak
• tujuh > tujuah
• rusuh > rusuah
• bayar > baya
• mahal > maha
• gunung > gunuang

And if you think about it, the debuccalization makes sense because P and U both uses the lips, I and T are made by raising the tongue, and A and K are on the back. They're homorganic.

Monophthongization also happens in Indonesian:

• cabai > cabe
• petai > pete
• kerbau > kebo