Looking on the internet deeply has found these results:

I will certainly not do it is the most popular phrase on the web.

I certainly won't do it 1124,000 results on the web	I will certainly not do it 1428,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
I certainly won't be following your obscure customs. And I certainly won't send her back to that laundry. And I certainly won't be forgotten there. I certainly won't say anything. I certainly won't miss that waistline. And I certainly won't be forgotten there. I certainly won't have any friends.	Mr President, I will certainly not have anything to say about legionella at this point. I will certainly not hold it against you. But I will probably manage to stop myself from asking you your views on voluntary set I will certainly not be authorizing a drone strike in Pakistan. And I will certainly not forget the matter when we take our leave today. I will certainly not be supporting this report on that basis, and I regret that situation. So, if any of you decide that you have to leave now, I will certainly not hold it against you. aside since you will certainly not be able to answer that question.

I certainly won't do it

1124,000 results on the web

I will certainly not do it

1428,000 results on the web

More popular!

Mr President, I will certainly not have anything to say about legionella at this point.
I will certainly not hold it against you.
But I will probably manage to stop myself from asking you your views on voluntary set
I will certainly not be authorizing a drone strike in Pakistan.
And I will certainly not forget the matter when we take our leave today.
I will certainly not be supporting this report on that basis, and I regret that situation.
So, if any of you decide that you have to leave now, I will certainly not hold it against you.
aside since you will certainly not be able to answer that question.