in·ef·fec·tu·al /ˌɪnəˈfɛkʧə(wə)l, ˈfɛkʃwəl/
 (a.)無效的,無益的,白費的
 In·ef·fec·tu·al a. Not producing the proper effect; without effect; inefficient; weak; useless; futile; unavailing; as, an ineffectual attempt; an ineffectual expedient.
    The peony root has been much commended, . . . and yet has been by many found ineffectual.   --Boyle.
 Syn: -- Inefficient; useless; inefficacious; vain; fruitless; unavailing; futile. See Useless, Inefficacious.
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 ineffectual
      adj 1: not sufficient to produce a desired result; "an ineffectual
             effort to block the legislation" [ant: effectual]
      2: not producing an intended effect; "an ineffective teacher";
         "ineffective legislation" [syn: ineffective, uneffective]
         [ant: effective]
      3: producing no result or effect; "a futile effort"; "the
         therapy was ineffectual"; "an otiose undertaking"; "an
         unavailing attempt" [syn: futile, otiose, unavailing]
      4: lacking in power or forcefulness; "an ineffectual ruler";
         "like an unable phoenix in hot ashes" [syn: ineffective,
          unable]