The sea looks very beautiful when the sun is shining on it. It can be very terrible when there is a strong wind. The sea is very big. It covers three quarters of the earth. The sea is also very deep in some places. There is one place, the sea is about 11 kilometers(公里)deep there. The highest mountain in the world is about 9 kilometers high. If that mountain was put into the sea at that place, there would be still 2 kilometers of water above it! In most parts of the sea, there are plenty of fishes and plants. Some live near the top of the sea. Others live deep down. There are also a lot of small living things. Lots of fishes live by eating them. The sea can be very cold. When people go down, the sea becomes colder and colder. Only some men can go down into the deep sea. But in 1970, five women scientists(科学家)lived in the deep sea for fourteen days. There are a lot of small living things in the sea, and they live by eating fishes.