the first four planets重点内容
The First Four Planets
Some planets are near to the sun.The sun is not a planet.
It is a star.It is very hot.It is also very big.It is much ( bigger ) than
any planet.In fact the sun is (the ) biggest thing in our solar system
The Earth is the third planet.The hottest planet is the first planet.The Earth is one of the (hottest ) planets.It is very near to the sun.
The Earth is (the ) biggest of the four planets.It is bigger (than ) the first,second and fourth planets.The first planet is (the ) smallest
It is much (smaller ) than the Earth.
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