unproductive [ˌʌnprəˈdʌktɪv]

例句:

• Natural history sank into a mire of unproductive pedantry.
  来自S. J. Gould
• The unproductive workers have supplied no saleable goods.
  来自WSJ
• I've had a very unproductive day.
  我这一天什么事都没干成。
  
• Research workers are well aware that much of their time and effort is unproductive.
  研究人员很清楚，他们的很多时间和精力全都是白费。
  
• One man's mystical haven for wealth is another's unproductive barbarous relic.
  一个人的神秘的财富庇护所则是另一个人的不毛的荒凉废墟.
  
• Learn to change when things become uninteresting and unproductive.
  来自SA