Mr Pronay Larma, the physical teacher of Rooppur High School is talking about health to his students.

"What things are necessary for good health?" he asks the students

"We need a lot of things, teacher," says Rushad. "We need healthy food, proper rest and sleep. We also have to be clean and tidy."

"Good!" says Mr Larma. "These are the things you need for good health. But another thing that you also need is regular physical exercise."

"What types of physical exercise can we do, teacher ?" asks Rayeed.

"Well," says Mr Larma. "There are different kinds of physical exercise. You can do them indoors as well as outdoors. In the house you can do some freehand exercises. That is, you can stretch different parts of your body. Outside, you can play, swim or simply walk."

"Why do we need physical exercise, teacher ?" asks Ranjan.

"Well", says Mr Larma, "The benefits of physical exercise are many. The greatest of them is that it keeps you fit for work. It also gives you energy, and makes you strong and cheerful. It teaches you regularity and discipline as well."