n.肺泡；牙槽
Around each alveolus there are capillaries, which are very small blood vessels. 在每一肺泡周围有许多毛细管，它们是很小的血管。
The lumen of the acinus is small and narrow, but that of the alveolus is large and distended. 单腺泡腔小而狭窄，但肺泡的腔却大而膨满。
Bone grafting of the alveolus is an essential step in the reconstruction of the orofacial cleft deformity. 牙槽突裂骨移植是口腔颌面部裂隙畸形重建的重要步骤。
