I just don't know enough to offer any definite opinion.
"You seem to have a very definite opinion about this, Doctor."
"She has a definite opinion, I should say, on almost anything," he answered.
They found her formidable, a woman of definite and strong opinions.
But you have not given me enough information to form more than one definite opinion.
Asked about the most important problems facing the church, 59 percent had definite opinions.
As to the subject we were discussing, I have no definite opinion myself.
He had definite opinions and was prepared to state them.
Maybe if you showed me again, I'd be able to form a more definite opinion.
She has definite opinions about why hot restaurants go cold.