By Rachel Mitchell Text Copyright 2018 by Rachel Mitchell

Unfamiliarity [Noun] (the fact of lacking knowledge or experience of something; not familiar).
His temporary shyness was due to his unfamiliarity with the environment.
Her unfamiliarity was not surprising; she had little acquaintance with the stock market.
Unexpected [Adjective] (surprising; not expected).
Life is unexpected.
His divorce was totally unexpected.
Unnecessary [Adjective] (not necessary; needless; unessential).
Some people feel that holiday insurance is unnecessary. It is unnecessary to cook for now. I am not hungry.
Unreasonable [Adjective] (something that is not reasonable; beyond what can be accepted).
The costs to rent a car in the city are unreasonable. He was offended by her unreasonable quarrel.
Universal [Adjective] (involving all people or things in the world).
Declining health is a universal characteristic of old age. English is a universal language and is used all over the world.
Unquestionable [Adjective] (not able to be doubted; obvious and undeniable).
The sincerity of her beliefs is unquestionable. His competence as a teacher is unquestionable.
Update = up to date [Verb] (to make something more modern).
The company decided to update its computer software.
The most recent weather update said it'll be sunny tomorrow.
Unthinkable [Adjective] (unimaginable (impossible to imagine or accept)).
It would be unthinkable to ask him to do that.
In the past, parents allowed their children to play freely in the street, but this is unthinkable nowadays.
Unscrupulous [Adjective] (dishonest, unfair and without moral principles).
He runs an unscrupulous business.
The innocent are often deceived by the unscrupulous.
LETTER V
Vast [Adjective] (very big/ extremely large).
The Sahara is a vast sandy desert. The Amazon is a vast rainforest.