endurance period的用法和样例：
例句
- Cancer should be suspected in persons who have any of the symptoms and signs for unaccountable causes and for an unreasonable period of time.
如果病人具有任何这些症状和表征，病因又难以说明，而且持续时间又很长，就应该怀疑患有癌症。 - If the scholastic achievement of highly intelligent children remains below average for an extended period, many teachers will fail to recognize their potential.
如果才智高的儿童的学习成绩在持续时间内始终低于平均水平，许多教师会不认可他们的潜力。
