The submarine is invulnerable to attack while at sea.

潜艇在海上是不会受到攻击的。

《牛津词典》

While at sea, a cargo is vulnerable to many dangers.

在海上，货物会遇到各种危险。

youdao

He taught mathematics on the university level and developed a system for calculating longitude while at sea.

他教授大学数学并且创制出一个用于海上计算纬度的体系。

youdao

There are several ways to reduce your communications costs while at sea and in port.

FORBES: How To Save Money On Calls And Data From A Cruise Ship

There is no simple technical solution to improve the passenger experience in connecting with the outside world while at sea.

FORBES: Cruise Ship Communications for Passengers Is About to Change

While at sea somewhere between Monaco and Barcelona, Forbes stock columnist Ken Fisher predicted the American stock market would pop during the second half of 2006.

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