darkens

例句:

• The photograph that the author develops darkens only gradually.
  来自NEWYORKER
• The sky darkens early in winter.
  冬天天黑得很早.
  
• It is here that Twain's satirical vision darkens.
  吐温那带有讽刺意味的眼光变得更加深沉了.
  
• He weakens the body, darkens the intellect, and debases the soul.
  他摧残人的身体, 蒙蔽人的理智, 腐化人的灵性.
  
• It falls below its net asset value when sentiment darkens.
  来自WSJ
• Cook for one minute, or until the mixture darkens slightly.
  来自BBC