It was Lalit Modi.

firstly is not a adjective its a time connective

Firstly is an adverb and does not have any tenses.

Firstly, this question is very dumb. Secondly, there was your sentence :)

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Firstly, I would have to think about your question, which seems a perfectly sensible question to me. Having thought about the question I would firstly suggest there are many sentences which could contain the word firstly, but these should do for now.

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