1、sea是名词，意思是大海、海洋，Most of the kids have never seen the sea.大多数的孩子甚至还没有见过大海。
2、Jack is a fisherman who goes to sea for two weeks at a time. Jack是个渔夫，他平均两周下海一次。
3、We spent a week by the sea this year.我们今年在海边度过了愉快的一周。
4、常见短语：a sea of something大量，put（out）to sea（船）启航、出海，in the sea在海上，sea water海水，sea level海平面，sea area海域。
