Infinitive words that begin with the letter /s/.
The adding of nasal prefix N- to the infinitive words that begin with the letter /s/ undergo a change of form on the prefix. For example spool, nasal N- + spool = nyepul.

basic word starting with /s/ consonant. The addition of N- nasal prefix with basic word starting with /s/ consonant undergoes consonant change at the beginning of basic word, for example spool, N- nasal + spool = nyepul.

Basic word started with consonant /s/. The addition of nasal prefix N- with basic word started with consonant /s/ change the first consonant letter of the basic word, for example spool, Nasal- + spool = nyepul.