sea

1. N-SING Thesea is the salty water that covers about three-quarters of the Earth's surface. 海洋['the' N, also 'by' N]

Most of the kids have never seen the sea. 这些孩子中的大多数从没见过大海。

2. N-PLURAL You use seas when you are describing the sea at a particular time or in a particular area. (某时、某区域的) 海[文学性]

He drowned after 30 minutes in the rough seas. 他在波涛汹涌的海里挣扎了30分钟后溺死了。

3. N-COUNT/N-IN-NAMES A sea is a large area of salty water that is part of an ocean or is surrounded by land. (作为海洋的一部分的或陆地围起来的) 海

...the North Sea. …北海。

4. PHRASE At sea means on or under the sea, far away from land. 在海上; 在海里

The boats remain at sea for an average of ten days at a time. 这些船平均每次在海上呆10天。

5. PHRASE If you go or look out to sea, you go or look across the sea. 到海上/向海上

...fishermen who go to sea for two weeks at a time. …每次出海两周的渔民们。