The tendency for sexually partnered couples to resemble each other is called:

Homogamy is a term used in sociology to describe the tendency for sexually partnered couples to resemble each other, in some culturally important way. It can be based on status, class, gender, ethnicity, or religion, or age.  It is a form of assortative mating.

it brings together the military and civilian sectors of society to harness the total power of the nation. it is the mechanism that facilitates the successful prosecution of any conflict.it brings together the military and civilian sectors of society to harness the total power of the nation. it is the mechanism that facilitates the successful prosecution of any conflict.

productive most commonly means: achieving or producing a significant amount or result.

explanation:

productive can also mean:

these depend on how the word productive is used. most likely productive will mean   achieving or producing a significant amount or result.