A dialogue between teacher and student about using a calendar

Student    : Good morning, Sir.

Teacher   : Good morning. How are you?

Student    : I am fine. Thank you, sir. How are you?

Teacher   : I am also fine. Thank you.

Student    : Sir, would you please tell me how to use a calendar?

Teacher    : Of course. Look at the calendar. What do you see?

Student    : Names of months and days.

Teacher   : Nothing else?

Student   : There are dates also. Some are black colour and some are red colour.

Teacher   : You have almost learnt. The dates and days tell you what date is in which day.

Student   : Colour of dates?

Teacher   : The red colours are holy days and the black colours are working days.

Student   : Thank you, sir.

Teacher   : No mention.