老年病人临床和CT诊断为脑转移瘤，其最常见原发灶部位
A．皮肤
B．结肠
C．前列腺
D．肺脏
E．肾脏
参考答案：D
David Beckham’s career ____ almost immediately when he was on the Manchester United’s youth team in 1992.
A．took up
B．got off
C．showed off
D．took off
简述湖泊及水库水的特点
