English: “And you shall make a fire-offering” is a general; “to fulfill a vow or as a freewill offering” is a particular; “for a pleasing aroma” returns and generalizes. Just as the particular is specified as not obligatory and standing, so everything that is not obligatory and standing.
Type of Learning
Klal ufrat uklal — voluntary offerings.
What Is Learned
Nesachim follow the pattern of vow and freewill: non-obligatory offerings of that class.