to and fro

副词 to and fro:

1. moving from one place to another and back again
   同义词：back and forth, backward and forward

1. Scythes swished to and fro.
   长柄大镰刀嗖嗖地来回挥动。
2. The ship was rolling heavily to and fro.
   那船晃来晃去很不平稳。
3. Trucks shuttled to and fro on the high ways.
   车辆在高速公路上穿梭行驶。
4. The cat made little rushes to and fro after the ball.
   猫追着球跑过来跑过去。