名词 rough water:

1. used of the sea during inclement or stormy weather

roughadj.粗糙的；粗略的，大概的；粗暴的；艰难的；讨厌的；不适的；汹涌的adv.粗糙地；粗暴地n.粗制品；暴徒；高低不平的路面vt.使粗糙；殴打；草拟rough map略图

1. It's hard to pilot a boat in rough waters.
   在汹涌的海面驾驶船只不容易。
2. The boat was rocking about on the rough seas.
   这只船在汹涌的海面上颠簸摇晃。