a pole的用法和样例：
例句
- Our flag is raised to the top of a pole by a rope and two pulley.
我们的旗帜被用一根绳子和两个滑轮升到了竿顶。 - He had put up a basket on a pole in the back yard.
他在后院一根柱子上安一个球篮。 - A West Indian dance in which the dancers keep bending over backward and passing under a pole that is lowered slightly each time.
林波舞一种西印度群岛的舞蹈，舞者须向后仰并穿过一支水平杆，每次都要比前一次仰得更低
