It was tough, but I finally had to decide.
The base word for the word "decision" is "decide."
'Choosen' is not a word, so do not use it at all, ever.
The base word of "decision" is "decide."
Will you ever decide what to do?
The word decided is a verb. It is the past tense of the verb decide.
It came from the Old English word Wicce meaning a sorceress and later, a woman who was supposed to have dealings with the devil
decide
Environmentalists must disabuse themselves of the notion that they can decide what is best for the rest of society.
The answer was somewhat disappointing. A somewhat unusual method was used to decide the contest winner.
If you are trying to decide something important, you might want to confer with an expert.
Decision is a noun. The verb form is decide, and the past tense is decided.
The word decide is a verb. The noun form is decision.