What should I use "task, job, chore, stint, assignment"?

task, job, chore, stint, assignment

These nouns denote a piece of work that one must do.
1) A task is a well-defined responsibility that is usually imposed by another and that may be burdensome: I stayed at work late to finish the task at hand.  
2) Job often suggests a specific short-term undertaking: "did little jobs about the house with skill" (W.H. Auden).  
3) Chore generally denotes a minor, routine, or odd job: The farmer's morning chores included milking the cows.
4) Stint refers to a person's prescribed share of work: Her stint as a lifeguard usually consumes three hours a day.  
5) Assignment  generally denotes a task allotted by a person in authority: His homework assignment involved writing an essay.

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