会议的法定人数是指( )。
A．实际到会的人数
B．使会议合法和生效的人数
C．到会者和缺席者的比例数
D．收到会议通知的人数
参考答案：C
把一个圆柱截成两个圆柱后，它的表面积一定比原来增加两个底面积。[ ]
Not until he retired from teaching three years ago ________having a holiday abroad.
(2012·辽宁，32)
A．he had considered
B．had he considered
C．he considered
D．did he consider
