守卫工作方针的内容是什么？
参考答案：
①严密防范。
②常备不懈。
③服务生产。
④保障安全。
地球上最长的纬线是[ ]
A、极点
B、极圈
C、赤道
D、回归线
My elder brother has gone to Tibet to work as a volunteer teacher. Influenced by him, I also want to become_______when I graduate from the university.
A．that
B．it
C．this
D．one
