Today, we went to the Museum of Natural History. In there, there were lots of interesting graphs, pictures, and things. The Universe was born about 15 billion years ago in the Big Bang. The planet that we live on, Earth, was formed.

Beforethe  Big Bang, there was nothing but darkness. But after the Big Bang, magma came out,then it began to rain. The magma hardened, and became rock. Then, because of water, there was a huge  puddle. This is nowadays the ocean. A long time ago,the continents were connected as one piece of  land  called Pangaea. If you look at the continents carefully, you can see that they used to be connected. 

Of course, besides Earth, there are lots of planets in our solar system. They are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. There was Pluto too, but it was too small to be called a planet, and it was revolving in an oval shape, not in a circle. When a planet turns on its axis, it's called a rotation. This takes one day. When it revolves around the sun, this is called a revolution. This takes one year. If you want to know something interesting, did you know that each planet (not including Earth) represent a Greekl God? Mercury is Hermes, Venus is Aprodite, Mars is Ares, Jupiter is Zeus, Saturn is Kronos, Uranus is Uranus, and Neptune is Poseidon.

An opening in the earth's crust through which magma is ejected is called a volcano. Baekdu Mountain and Halla Mountain on the Han Penisula were made by volcanic eruption. Nowadays, Baekdu and Halla Mountain are active volcanoes. Inactive volcanoes are volcanoes that stopped working.Cyano bacteria are living cells that produce oxygen through photosynthesis.

Since these little cells filled the earth with oxygen, there were various living things. About 6,500,000 years ago, dinosours disappeared.There were two types of dinosours, herbivorous and carnivorous. the herbivorous ones ate grass, while the carnivores ate meat. Acrocanthosaurus is a good example of a carnivorous dinmosaur. They were frightening and ate meat. Their main feature was the long saw-like protusion that developed from their neck to their tailbone. I was amazed at how the universe was formed, and how interesting thed Earth looked 4.6 billion years ago.

Very good, excellent vocabulary!

Try to divide your writing into paragraphs.