Noun
The last syllable but one of a word; the syllable preceding the final one.
Source: Webster's dictionaryIf the penult has a schwa, then stress moves to the ante-penultimate syllable if there is one, even if that syllable has a schwa as well; if the word is disyllabic, the stress is final. Source: Internet
In disyllabic stress with a closed penultimate syllable, such as tinggal ('stay') and rantai ('chain'), stress falls on the penult. Source: Internet
If the penult is light, accent is placed on the antepenult; if it is heavy, accent is placed on the penult. Source: Internet
Thus, regular verbs ending with -n and the great majority of words ending with -s are stressed on the penult. Source: Internet