give me the rules for changing  the assertive sentence into direct to indirect speech

Various rules to convert direct into reported speech are:

• A simple present becomes a simple past;

• A present continuous becomes a past continuous;

• A present perfect becomes a past perfect.

• The 'shall' of the Future tense is changed into 'should'.

• The 'will' of the Future tense is changed into 'would' or 'should'.

• The pronouns of the Direct speech are changed wherever necessary, so that their relations with the reporter and his hearer, rather than with the original speaker, are indicated.

• Words expressing nearness in time or place are generally changed into words expressing distance. For instance, now becomes then, ago becomes before, tomorrow becomes the nest day and last night becomes the night before.

• The tenses may not change if the statement is still relevant or if it is a universal truth.