sea

詞意辨析：

sea, ocean

這兩個名詞均可表示“海”之意。
sea: 普通用詞，可用複數形式表單數意義。sea所指的面積要比ocean小得多。sea也可是ocean的一部分。
ocean: 指把海作為一個整體，是海的總稱，即海洋。

字典網

英文解釋：

名詞 sea:

1. a division of an ocean or a large body of salt water partially enclosed by land
2. anything apparently limitless in quantity or volume
   同義詞：ocean
3. turbulent water with swells of considerable size

形容詞 sea:

1. relating to or characteristic of or occurring on the sea or ships

英文造句：

1. The moonlight shone on the calm sea.
   月光映在平靜的海面上。
2. Nautilus is a small sea animal.
   鸚鵡螺是種小型海洋動物。
3. I stood amid a sea of corn.
   我站在茫茫一片莊稼之中。
4. I'm all at sea; I've no idea how to repair cars.
   我手足無措，不知道怎樣修理汽車。
5. She tried to understand the instructions, but she was completely at sea.
   她費盡力氣想看懂那些說明文字，卻全然不知所云。
6. The sea covers nearly three-fourths of the world's surface.
   海洋幾乎占地球表面的四分之三。