■在某些习语中通常不用冠词。如： put to sea开航，起航 http://yingyu.chazidian.com go to sea (as sailors) （当水手）出海 be at sea = be on a voyage (as passengers or crew) （作为旅客或船员）乘船航行 ■除此之外原则上要和冠词。如： I like to bathe in the sea. 我喜欢在海里游泳。 The sea calmed down. 海水平静下来。 The sea was now calmer. 海比较平静了(http://yingyu.chazidian.com)。 My love for you is deeper than the sea. 我对你的爱比海还深。 Aquanauts go to the floor of the sea. 海洋研究人员到海底去探查。 The sea can be blue or green or grey. 海水可以是蓝色、绿色或是灰色。 A damp breeze from the sea usually means rain. 海上吹来的湿风通常意味着要下雨。 The aeroplane out of control and fell into the sea. 飞机失去控制坠入海中。 A man fell overboard into the sea and was drowned. 一名男子从船边坠人海中给淹死了。 There was an icy easterly wind blowing off the sea. 有一股由东边海上吹来的凛冽的寒风。