明代是四唐分期说的定型时期，代表论著是（）。
参考答案：《唐诗品汇》
Her question was so difficult that I could hardly make any ________ of it at all. [ ]
A. explanation
B. meaning
C. sense
D. idea
高强度紫外线消毒灯要求（）。
A．功率＞30W灯，≥90μW/cm2
B．功率30W灯，＞180μW/cm2
C．臭氧产量＜1mg/h
D．臭氧产量＞25mg/h
E．功率30W灯，＞160μW/cm2
