Doubtful in a sentence and paraphrased in a sentence.

Here are examples of the word/phrase "doubtful" used in a sentence and paraphrased in a sentence...

Don't be doubtful about your potential.

Don't be dubious about your potential.

When he saw how strong his opponent was, he became doubtful about victory.

When he saw how strong his opponent was, he became skeptical about victory.

The teacher was doubtful about all of her students making it to class on time.

The teacher was dubious about all of her students making it to class on time.

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