The negative form of the sentence is:
Original sentence: When Rabindra’s Mother passed away he was inconsolable.
Negative sentence: When Rabindra’s Mother passed away he was not consolable.
Explanation:
To change this sentence to negative, we focus on the adjective ‘inconsolable.’ The prefix ‘in-‘ in ‘inconsolable’ already makes it negative, meaning ‘not able to be consoled or comforted.’ To negate this, we remove the prefix ‘in-‘ and add ‘not’ before the adjective.