空气流通

• Maintaining good ventilation indoors ; and
  保持空气流通及
• 5 . maintain good indoor ventilation
  5 .保持室内空气流通
• Maintain good indoor ventilation by opening windows from time to time
  经常打开窗户，保持室内空气流通。
• Maintain good indoor ventilation
  保持室内空气流通。
• To prevent tuberculosis , you should ensure good indoor ventilation
  要预防肺结核，记得要保持室内空气流通。
• Maintain good indoor ventilation
  保持室内空气流通
• Good ventilation should be maintained
  保持空气流通
• Second , make sure there is good ventilation , both at home and at work
  第二，要保持室内空气流通，防止病源滋生
• Maintain good ventilation of air
  保持空气流通。
• Exercise in an environment with good ventilation and suitable temperature
  在空气流通及温度适中的环境进行运动。