海上副热带高压中部的天气特点是（）
A．风弱，闷热，多阵雨
B．风强，对流旺盛，多阵雨
C．风弱，闷热，万里无云
D．风强，干爽，万里无云
参考答案：C
Not until I began to work _____ how much time I had wasted. [ ]
A. didn't realize
B. did I realize
C. I didn't realize
D. I realized
紫外一可见分光光度法用于含量测定的方法一般有（）、（）法和标准曲线法。
