阅读短文,在空白处写出各单词的正确形式,单词的第一个字母已给出(初二)

阅读短文,在空白处写出各单词的正确形式,单词的第一个字母已给出(初二)
There have been many great inventions that changed the way we live.The f____ great invention was one that is still very i____ today----wheel.This made it e____ to carry heavy things and to travel long distance.For hundreds of years after that there were f____ inventions that as important as the wheel.Then in the early 1800's the world started to c_____.There was l_____ unknown land left in the world.People didn't have to e____ much any more.They began to work instead to make life b____.In the second half of the 19th c____ many great inventions were made.Among then were camera,the electric light and the radio.These all become a big p____ of our life today.