Advice doesn't normally come cheap, but this piece is for free...
通常来说,忠告都是价值不菲的,但这个是免费赠送的。。。
First the electroencephalograph (which is simply a device for recording the electrical activity of the brain by attaching electrodes to the scalp) shows that while there is a change in the pattern of activity during sleep,
第一点,脑电图记录仪(不过是一种把电极接到头皮上记录脑电活动的仪器)显示,人在睡眠时大脑活动的方式有变化,