यामाश्चत्वारश्चत्वारो मर्त्यानामहनी उभे ।
पक्षः पञ्चदशाहानि शुक्लः कृष्णश्च मानद ॥ १० ॥
yamah-three hours; catvarah-four; catvarah-and four; martyanam-of the human beings; ahani-duration of day; ubhe-both day and night; paksah-fortnight; panca-dasa-fifteen; ahani-days; suklah-white; krsnah-black; ca-also; manada-measured.
It is calculated that there are four praharas, which are also called yamas, in the day and four in the night of the human being. Similarly, fifteen days and nights are a fortnight, and there are two fortnights, white and black, in a month.