I learned two big things first one was about solar system, and the next one is about history of living things. The Universe was formed about fifteen billlion years ago, and the Earth was formed about 4.6 billion years ago. Long time ago, the Earth's continents were connected as one piece of land. This is called Pangaea. There are 8 planets starting with the planet closest to the Sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Actually there was one other planet named Pluto, but people except it in the solar system. There were astromical chart was already drawn in the goguryo, and also in the Joseon Dynasty. an opening in the earth's crust through which magma is ejected is called a volcano. Baekdu mountain and Hanra mountain on the Han Peninsula were made by volcanic eruption. Now it's about history of living things Cyanobacteria are living cells during the Precambrian Era and produce the oxyzen through the photosyntheis. Dinosaurs were appeared in Mesozoic Era. The most important carnivore dinosaur is Tyrannosauruses. And they eat meat. The most important herbivorous dinosaur is Stagosarus it protect themselves by the horn. There are many other dinosaurs but I don't know all of them.  My favorite part in here is about Pangaea, and I want to figure it our when I'm travling.