decisive
vulcanologist.
you call them a computer tech
A person who knows three languages is typically referred to as a trilingual.
Educated.
a animal wisperer
An automotive technician.
A person who knows the dictionary by heart is often referred to as a lexicomane or a lexiconophilist.
because no one knows
an accessory after the fact may be what you are looking for
Counterfeit money ...
A very talented person. Multi-lingual.Most probably more talented than YOU.
Someone who knows the number you want or directory enquiries.