正常人一般左肺由几个肺段组成
A．7B．8C．9D．10E．11
参考答案：B
解析： 右肺有10个肺段，左肺有8个肺段。
121. I was uncertain of my success. Which of the following can replace the underlined word?
A．willing
B．not sure
C．certainly
D．not certainly
骑摩托车的人戴安全帽，可以减少头部受伤。
