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I was not sure with his answer is the most popular phrase on the web.

I am not sure with his answer 1581,000,000 results on the web	I was not sure with his answer 1899,000,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
I'm not sure my answers really satisfied them. author. You said the text would be aligned but I am not sure with what. I am not sure whether I should answer your question, as it is more of a polemic comment. I presume he has answered many of the questions the public in general have been asking, but I am not sure if those answers will be to their satisfaction. I am not sure that brief answers will help me in future if it means I get these kinds of questions. I am not sure your answer will satisfy my constituent, Mrs P. Adams of Nantwich, in several respects. I'm sure his answer differs from mine.	I'm not sure my answers really satisfied them. I'm sure his answer differs from mine. Honestly, I'm not sure what answer I wanted. Still not sure that answers my question. I'm not sure I can answer that without getting in trouble. I'm not sure that's the answer. There is one interesting difference, though I'm not sure it answers your question. I am not sure your answer will satisfy my constituent, Mrs P. Adams of Nantwich, in several respects.

I am not sure with his answer

1581,000,000 results on the web

I was not sure with his answer

1899,000,000 results on the web

More popular!

I'm not sure my answers really satisfied them.
author.
You said the text would be aligned but I am not sure with what.
I am not sure whether I should answer your question, as it is more of a polemic comment.
I presume he has answered many of the questions the public in general have been asking, but I am not sure if those answers will be to their satisfaction.
I am not sure that brief answers will help me in future if it means I get these kinds of questions.
I am not sure your answer will satisfy my constituent, Mrs P. Adams of Nantwich, in several respects.
I'm sure his answer differs from mine.

I'm not sure my answers really satisfied them.
I'm sure his answer differs from mine.
Honestly, I'm not sure what answer I wanted.
Still not sure that answers my question.
I'm not sure I can answer that without getting in trouble.
I'm not sure that's the answer.
There is one interesting difference, though I'm not sure it answers your question.
I am not sure your answer will satisfy my constituent, Mrs P. Adams of Nantwich, in several respects.