孩子们在炎热的阳光下玩耍而没有涂防晒霜，皮肤完全暴露在紫外线中。

The children played in the hot sun without sunscreen, leaving their skin completely ___unprotected from UV rays.

游客们在没有防护措施的悬崖边拍照很危险。

Tourists taking photos near the ___unprotected cliff edge is very dangerous.

医生建议年轻人避免无保护措施的性行为以降低意外怀孕的风险。

Doctors advise young people to avoid ___unprotected sex to reduce the risk of unplanned pregnancy.