The Third Conditional in Tamil grammar, or the ‘Mūṉṟām koṇṭiṣaṇal’, is used to talk about situations that did not happen in the past and their imagined consequences. It is structured by using the past perfect tense for the if-clause (hypothetical part) and would have + past participle for the main clause (resultant part). These exercises focus on understanding and applying the third conditional in Tamil grammar.