1 00:00:15,089 --> 00:00:33,729 As you know, all machines need energy to work. 2 00:00:33,729 --> 00:00:43,729 In our age, our machines need useful energy from people. 3 00:00:43,729 --> 00:01:04,409 There are two types of machines. Simple machines and complex machines that have more than a combination of other machines. 4 00:01:04,409 --> 00:01:09,409 For example, our car is a simple machine. 5 00:01:09,409 --> 00:01:48,680 And now, we will show you our machines in action. 6 00:01:48,680 --> 00:02:02,129 For listening, we hope you like our video.