mist (something) over/up          
phrasal verb with mist verb uk/mɪst/ us/mɪst/
 mainly UK (US usually fog over/up)(使)蒙上水汽,(使)结满雾气 
If something that you can see through mists over/up, it becomes covered with a thin layer of liquid so that it is more difficult to see through.
  Open the window when you have a shower to stop the mirror misting over. 淋浴时打开窗,免得镜子蒙上水汽。 
 The steam from the kettle misted up her glasses. 水壶里冒出的水蒸气使她的眼镜变得雾气蒙蒙。 
 See also: steam (something) up
  (眼睛)含着泪水;泪眼婆娑
If your eyes mist over/up, they fill with tears.