单词：shuttling
n. 往复运动；梭动
v travel back and forth between two points
词型变化：名词复数形式 : shuttlings
shuttling的用法和样例：
例句
- Trucks shuttled to and fro on the high ways.车辆在高速公路上穿梭行驶。
- We shuttled the passengers to the city center by helicopter.我们来来回回地用直升机把旅客运送到市中心。