Aerobic exercise - any kind of physical exercise of relatively low intensity, where the oxygen is used as the main source of energy for the maintenance of muscle motor activity [1]. Aerobic means "with oxygen", meaning that one oxygen is sufficient to adequately meet the demand for energy during exercise. [2] Usually mild to moderate exercise intensity that can be supported mainly by aerobic metabolism, can be performed over a long period of time. [3] The opposite of aerobic exercise is anaerobic exercise. Some of the aerobic exercises include walking or hiking, jogging, running in place, swimming, skating, climbing stairs, boating, skateboarding, roller skating, dancing, basketball, tennis
10) The exercises were being checked by students while the bell was ringing.
11) My teacher was asked to help me.
12) I was given a good mark by the teacher.
13) The roof of the house will be painted by the boys.
14) A book was given to Nick by Tom for his birthday.
15) She was shown the way by a boy.
16) Stories are told by our mother every evening.
17) The branch of the tree was broken by the elephant.
18) The dishes were being washed by Helen and the music was being listened to by Betty.
19) The plants have just been watered by me.
20) Tom has been waited by them since morning.