遇到紧急情况时，人体的战斗或逃跑反应会加速心跳。

In emergencies, the ___fight-or-flight response makes your heart beat faster.

当老板突然质问时，他陷入了战或逃的困境，不知该争辩还是道歉。

When the boss suddenly questioned him, he was in a ___fight-or-flight dilemma, unsure whether to argue or apologize.