问题
选择题
Scientists have discovered amazing evidence showing how the human body rebuilds _______ while we sleep.
A．us
B．ourselves
C．it
D．itself
答案
Ｄ
考查反身代词用法.根据题意,科学家发现了惊人的证据,证明了当我们睡着时人类身体是如何修复自身的.句中反身代词指代人的身体本身,故用itself,选D.