vagina synovialis intertubercularis

例句：

1. 1. The vaginal epithelium is the thin layer of cells that lines the vagina.
   阴道上皮是覆盖阴道的薄层细胞。
2. 2. The vaginal epithelium is responsible for protecting the vagina from infection.
   阴道上皮负责保护阴道免受感染。
3. 3. During menstruation, the vaginal epithelium sheds to allow blood to flow through.
   月经期间，阴道上皮会脱落以便血液流动。