单词penis-s
If the legs are filled with blood, the blood in the waist can causes an erection, entering the penis"s erectile tissue.
如果腿充满了血液，腰部的血液则进入阴茎的勃起组织，可能导致勃起。
Essentially circumcision dramatically reduces the amount of the penis"s surface area that is exposed to viruses and bacteria.
根本上说，环切手术可以大大减少阴茎暴露在病毒和细菌中的区域。