tracts

• The digestive tract is inhabited by many species of parasites .
  寄生于消化道的寄生虫，种类很多。
• The atmosphere is often highly irritating to the eyes and to the respiratory tract .
  大气常会刺激眼睛和呼吸系统。
• The respiratory tract is an important portal of entry for respiratory viruses .
  呼吸道是呼吸道病毒入侵的重要门户。
• Even small tract houses in regimented rows appeared well cared for .
  甚至一排排象兵营似的小片房屋看上去也管理很好。
• If you do stop, she takes out her tracts and begins to speak .
  然而，如果你停下了脚步，她就会拿出那些小册子聒噪起来。
• The secretory system of the respiratory tract is probably the most appreciated .
  呼吸道的分泌系统可能是最先被意识到的。
• Mrs. stowe wrote a tract for the times, in the hope of arousing public sentiment .
  斯托夫人为她那个时代写了一篇论文，希望能够激起公众的情绪。
• A rust or prune juice in nasal discharge colour indicates blood originating from lower respiratory tract .
  铁锈色或深紫红色鼻液表示血液来自下呼吸道。
• Acute sinusitis is usually initiated by an acute respiratory tract infection of viral etiology .
  急性鼻窦炎常常是由病毒性病因的急性呼吸道感染而发生。