Look at these sentences.

Guwani is writing.

I will help Guwani.

This is Guwani’s book.

Here, you have the same word, ‘Guwani’ shown in three different relations.

In (1.) Guwani is doing something.

In (2.) Something is going to be done to Guwani.

In (3.) Something is said to belong to Guwani.

Such relations are expressed in language by what, is called Case.

In (1.) Guwani is the subject of the sentence, and is said to be in the Nominative case.

In (2.) Guwani is the object of the sentence, and is said to be in the Objective case.

In (3.) Guwani is shown to be in the possessor of something, and is said to be in the Possessive case.

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