RIGHT

WRONG

menghafal

hafal

nghafal, khafal, tghafal

mencari

cari

ncari, tcari

mengganggu

ganggu

ngganggu, kganggu, anggu

mengenal

kenal, enal, ngenal

genal, tgenal

memukul

pukul, mukul

ukul

menyiapkan

siap(kan),nyiap(kan)

yiap(kan), iap(kan), tyiap(kan)

Rule #1:

Remember: ng and ny function as SINGLE NASALS ( and in the phonetic alphabet);
DON'T BREAK THEM DOWN into n plus g or n plus y. This is how you get the incorrect roots tgenal, tghafal, yiapkan, etc.

Rule #2:

Indonesian roots DO NOT begin with nasal plus consonant (such as nghafal, ncari, etc.).

Rule #3:

Roots that start with a, e, i, o, u are preceded by the prefix meng-, never by any other nasal (so ukul could not be a root for memukul, or iap(kan) for menyiapkan).

THE GENERAL RULE

(definitions: NASAL = m, n, ng, ny; VOWEL = a, e, i, o, u; CONSONANT = all others)

A. If you have the sequence me[NASAL] plus CONSONANT, the root starts with that consonant; there will be no other possible roots.  
Also, if you have the sequence me[r,l,y, or w], the root starts with r, l, y, or w. There will be no other possible roots.
   

B. If you have the sequence me[NASAL] plus VOWEL, you have more than one
     possibility for the root:

1. The root starts with the nasal itself:

2. The root starts with a voiceless consonant that disappears; you can tell which consonant has disappeared by looking at the nasal: m > p; n > t; ng > k; ny > s 

3. IF AND ONLY IF THE NASAL IS ng, there is ALSO the possibility that the root starts with the VOWEL which comes after the ng.