under sail

基本解释

You can't really know a boat until you've been on it under sail.
你若没有驾它出海，就不可能真正了解这艘船。
Once the power begins to run down, an afternoon or so at sea under sail will recharge the batteries, says William Ray, Paracas’s director of engineering.
帕拉卡斯工程总监威廉姆•雷说，一旦电源开始耗尽，在海上扬帆一个下午左右就可以给电池充电。
When the boat is under sail, water forced through the duct turns the blades of a small hydroelectric generator that charges a bank of lithium-ion batteries.
当船在航行时，被迫通过管道的水旋转一个小型水轮发电机的桨叶，发电机给一组锂离子电池充电。

An old expression of the sailors that is still heard is to sail under false colors.
Today,a person,not a ship, is said to sail under false colors.

Very few ships worldwide sail under U.S. flag and with an all-American crew.
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The Tour 2 was built in South Korea, and set sail in 2007 under the name of the Tour (without the 2), flagged to Iran.
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