378. As you sleep you pass through a sequence of sleep states—light sleep, deep sleep and REM (rapid eye movement) sleep—that repeats approximately every 90 minutes.

译文

你睡觉时会经历一系列连续的睡眠阶段——轻度睡眠、深度睡眠以及REM（眼部快速运动）睡眠——这些睡眠阶段大约每90分钟重复一次。

点睛

as此处引导的是时间状语从句，意为“正当……时，随着”。如：
I saw you as I was getting off the bus. 我要下公交车的时候看到了你。
pass through意为“经过”。如：
I came to say hello as I was passing through. 我路过此地，顺便来跟你打个招呼。
He passed through a difficult period after the divorce. 他离婚后经历了一段困难时期。
a sequence of意为“一系列，连续的”。如：
I was confused by a sequence of dance movements. 我被连续的舞蹈动作给弄迷糊了。

考点归纳

pass的常见短语有：
pass away意为“死”，是委婉的表达，相当于中文的“去世”。如：
Her grandfather passed away last year. 她的祖父去年去世了。
pass sth. down意为“将某物代代相传”。如：
Such knowledge should be passed down over the centuries. 这样的知识应该世代相传。
pass over sth.意为“忽略某事物，回避某事”。如：
She chose to pass over his rude remarks. 她选择对他的粗话不予理会。