问题描述：
Speculations about its nature have been going on for literally thousands of years,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.
新概念四19课,
it looks very much as if sleeping is not simply a matter of giving the body a rest.
这个 it指的是什么?
新概念四19课,
it looks very much as if sleeping is not simply a matter of giving the body a rest.
这个 it指的是什么?
问题解答：
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