Karnatakabhashabhushana 8.9

[Tense-suffixes apply] in their own tense.

The suffixes denoting the past and so forth are to be prescribed in their own respective tense. This is what is meant: the past tense suffix is to be prescribed in past time; the present tense suffix in present time; the future tense suffix in future time. For example:

In the past:

puṭṭidaṁ (‘he was born’);

puṭṭidar (‘they were born’).

In the present:

puṭṭidapaṁ (‘he is being born’);

puṭṭidapar (‘they are being born’).

In the future:

puṭṭuvaṁ (‘he will be born’);

puṭṭuvar (‘they will be born’).

Likewise also in the second and first persons.