worth while
  值得做
  While n.
  1. Space of time, or continued duration, esp. when short; a time; as, one while we thought him innocent.  “All this while.”
     This mighty queen may no while endure.   --Chaucer.
  [Some guest that] hath outside his welcome while,
  And tells the jest without the smile.   --Coleridge.
     I will go forth and breathe the air a while.   --Longfellow.
  2. That which requires time; labor; pains.  [Obs.]
     Satan . . . cast him how he might quite her while.   --Chaucer.
  At whiles, at times; at intervals.
  And so on us at whiles it falls, to claim
  Powers that we dread.   --J. H. Newman.
  -- The while, The whiles, in or during the time that; meantime; while. --Tennyson.
  Within a while, in a short time; soon.
  Worth while, worth the time which it requires; worth the time and pains; hence, worth the expense; as, it is not always worth while for a man to prosecute for small debts.
  Worth, a.
  1. Valuable; of worthy; estimable; also, worth while.  [Obs.]
     It was not worth to make it wise.   --Chaucer.
  2. Equal in value to; furnishing an equivalent for; proper to be exchanged for.
     A ring he hath of mine worth forty ducats.   --Shak.
     All our doings without charity are nothing worth.   --Bk. of Com. Prayer.
     If your arguments produce no conviction, they are worth nothing to me.   --Beattie.
  3. Deserving of; -- in a good or bad sense, but chiefly in a good sense.
     To reign is worth ambition, though in hell.   --Milton.
     This is life indeed, life worth preserving.   --Addison.
  4. Having possessions equal to; having wealth or estate to the value of.
     At Geneva are merchants reckoned worth twenty hundred crowns.   --Addison.
  Worth while, or Worth the while. See under While, n.