题目

The boy lay in bed ____, listening to the songs on the radio.  A. awoke B. awake C. wake D. woke     答案：Bawake在这里是形容词作状语，相当于he was awake的概念，表达状态。18．（1）解不等式组：$\left\{\begin{array}{l}{2x-2≤x}\\{x+2＞-\frac{1}{2}x-1}\end{array}\right.$（2）化简：$\frac{{a}^{2}}{{a}^{2}{-b}^{2}}$÷$\frac{a}{a+b}$．