Я не могу с уверенностью сказать, б

Я не могу с уверенностью сказать, будет ли он на собрании, но если он придет, то обязательно выступит в прениях.

Results (English) 1:

I can't say for sure whether he will be at the meeting, but if he comes, he will speak in the debate.

Results (English) 2:

I can not say with certainty whether it will be at the meeting, but if he comes, he will certainly speak in the debate.

Results (English) 3:

I cannot say with confidence, whether it would be at the meeting, but if it comes, it is essential to speak in the debate.