oceans
The ocean is the sea.
the sea
There were few sights as beautiful as the calm ocean on a warm night.
很少有景色能与温暖夜晚下风平浪静的大海媲美。
new technology used to explore the deep ocean.
用以探索深海的新技术。
a fish's habitat on the ocean floor.
一条鱼在海底的栖息地。
An ocean is one of the five very large areas of sea on the Earth's surface.
a sea
They spent many days cruising the northern Pacific Ocean.
他们花了很多天巡游北太平洋。
a small island in the Indian ocean.
印度洋中的一座小岛。
If you say that there is an ocean of something, you are emphasizing that there is a very large amount of it.
I had cried oceans of tears.
我已哭得泪流成河。
a drop in the ocean
If you say that something is a drop in the ocean, you mean that it is a very small amount which is unimportant compared to the cost of other things or is so small that it has very little effect on something.
His fee is a drop in the ocean compared with the real cost of broadcasting.
和广播的实际成本相比,他的费用简直是沧海一粟。