No one knows for certain what happened, but it's a fair bet that it was not an accident.
没有人知道究竟发生了什么,但几乎可以肯定这并非意外。
and one odd finding that makes the problem puzzling is that it looks very much as if sleeping is not simply a matter of giving the body a rest.
一项使人对这个问题感到困惑的奇怪的发现是,睡眠在很大程度似乎并不仅仅是为了使身体得到休息。