Machines make our lives easier. We use them to do work, to travel, to communicate, and to have fun. Some machines are simple, with only one or two parts. Other machines are complex, with many parts that work together. What are the machines bellow called?, What do we do with these machines?, Which of these machines do you use?, What other machines do you use?. People invented the first machines a long tome aga. They were si,ple tools made of stone, wood, or bone. About two nillian years ago people made stone axes with wooden handles. They used these tools to cut wood. People also used stone and animal bone to make knives and arrows. To shoot their arrows they used bows made with long pieces of wood. People used simple levers to move heavy object like rocks. They pit one end of a long stick of wood under a big rock, and they put a small rock under the stick. [download]
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