Synonyms for construct include build, create, fabricate, form, or produce.
Construct is one word that means to build
There is no one-word substitute in English for "son-in-law."
The word you want is florist.
Sportsmanship is a word substitute for spirit of game
The word metalworking is one word.
Sentence: Within the purview of our department's responsibilities, we are tasked with overseeing all financial transactions and budget allocations.
eat, use
The word that works is idiot.
One possible substitute for "their" is "his" or "her" depending on the gender of the person/people being referred to. Another substitute can be "its" when referring to a non-human object or entity.
Elevate
Traditionalist
Omnipresent