it v-link ADJ of n to-inf
The 'kind' group
These adjectives indicate that the action indicated in the to-infinitive clause is judged to be good in some way, for example because it is brave or wise.
big brave clever courageous decent fair generous good great kind lovely nice prudent responsible right sensible smart sweet thoughtful wise
'I'm very grateful to you, Harry,' she said softly. 'It was big of you to take the risk.'
It was courageous of him to speak out.
It was very kind of him to think of me when there are so many to think of.
It was nice of you to come.
I think it was wise of your father to do what he did.