#hours  a period of time assigned for work; "they work long hours"
  supertype:  work_time  a time period when you are required to work
  subtype:  work_shift__shift__duty_period  the time period during which you are at work
     subtype:  spell__go__tour__turn  a time for working (after which you will be relieved by someone else); "it's my go"; "a spell of work"
     subtype:  trick.work_shift  a period of work or duty
     subtype:  watch.work_shift  a period of time (4 or 2 hours) during which some of a ship's crew are on duty
        subtype:  dogwatch  either of two short watches: from 4-6 pm or 6-8 pm
        subtype:  graveyard_watch__graveyardwatch__middle_watch__midwatch__night_watch__nightwatch  a watch during the night (as from midnight to 8 a.m.)
     subtype:  day_shift__dayshift  the work shift during the day (as 8 a.m. to 4 p.m.)
     subtype:  swing_shift__swingshift__evening_shift__eveningshift  the work shift during the evening (as 4 p.m. to midnight)
     subtype:  graveyard_shift__graveyardshift__night_shift__nightshift  the work shift during the night (as midnight to 8 a.m.)
     subtype:  split_shift__splitshift  a working shift divided into two periods of time with several hours in between

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