按下一个键后立即放开，产生IRQ1的个数是( )。
A．随机的
B．1
C．2
D．3
参考答案：C
The_________look on his face suggested that he was satisfied with our work. [ ]
A. pleased
B. pleasure
C. pleasing
D. please
中国画讲究边框，如同西方画讲究装裱。
