277. While there's no question that continuous stress is harmful, several studies suggest that challenging situations in which you're able to rise to the occasion can be good for you.

英语四级译文:
尽管人们对持续的压力有害健康的观点不加怀疑，却有几项研究表明，如果你能在富有挑战性的境遇中随机应变，这种境遇将对你有好处。

四级词汇讲解:
本句的主干是studies suggest that while引导的是让步状语从句，其中that引导的是主语从句;主句中that引导的是suggest的宾语从句，其中in which引导的in which you're able to rise to the occasion是situations的定语从句。

there's no question的意思是“毫无疑问”。如:
He's the best; there is no question about it，他是最棒的，这毫无疑问。

rise to the occasion的意思是“善于处理突如其来的困难，随机应变”。

be good for的意思是“对…有益的，有帮助的”。如:
Regular exercises are good for your health.坚持运动有益健康。

英语四级考点归纳:
while常见用法如下:

※ 用于引导时间状语从句，意为“当……时”。如:
We arrived while they were having dinner.他们吃饭的时候，我们到了。

※ 用于引导让步状语从句，意为“虽然，尽管”。如:
While she is just a little girl, she can be extremely diff cult to deal with.她尽管只是个小女孩，却也很难对付。

※ 用作转折连词，意为“而，却”。如:
Lisa is good at science, while her sister is good at literature.莉萨擅长理科，而她的妹妹则擅长文学。