241 Don't sit on the floor.
242 Why?
243 I like to do so.
244 It's a bad habit.
245 Here comes the bus.
246 Hurry up!
247 It's no good for your eyes.
248 Don't wait here.
249 Don't hurry.
250 Don't play football just after lunch.

a: Bobbie, don't sit on the floor.
Why?
It's dirty.
But I like to do so.
It's a bad habit.

b: Look! Here comes the bus.
Hurry up!
Don't read in the bus.
Why?
It's no good for your eyes.
Thank you.

c: What's the time?
It's four in the afternoon.
Let's wait for the bus.
Don't wait here.
Why?
Here is no bus now.
Let's walk home.
Ellen, let's go to school.
Don't hurry.
Why?
It's Sunday today, there is no lesson.
Oh, yes! Let's go to the zoo.

d: Don't read in the dark.
Why?
It's no good for your eyes.
Thank you.
Don't play football just after lunch.
Why?
It's no good for your health.
Thank you.