主帆

To shift the mainsail from one side to the other when sailing with the wind behind; also "gybe".

顺风行驶将主从船的一转到另一。

Then, as they were just passing the Round Tower, the young man shouted: "Stand by there to lower the topsails and jib; brail up the spanker!"

，船正在驶过圆塔，青年就喊道:“注意，准备收主，后和三角！”