商品住房通过市场化途径建设，可在市场上自由交易，主要面向中等收入以上家庭。（）
参考答案：对
_______ read newspapers for pleasure,but also to improve their minds. [ ]
A. Not only old men
B. Not only old men do
C. Not only do old men
D. Old men not only do
只能用角频率这个物理量来衡量交流电变化快慢的程度。
