sledding

名词 sledding:

1. the sport of riding on a sled or sleigh
2. advancing toward a goal
   同义词：going

动词 sled:

1. ride (on) a sled
   同义词：sled, sleigh

1. Kathy had hard sledding in her math course because she was poorly prepared.
   凯西的数学很难进步，因为她的基础太差。