A fortnight was 14 days long and two fortnights made up the duration of a moon cycle which is approximately 28 days.
(A fortnight; was; 14 days long) (two fortnights; made up; the duration of a moon cycle) (a moon cycle; is; approximately 28 days)
A fortnight two fortnights a moon cycle
was made up is
14 days long
the duration of a moon cycle
approximately 28 days