Answer and Explanation:
2. "Paul tied a knot." This is a complete sentence.
3. "Caught the ball for the third out." This is a fragment sentence.
You can easily detect a complete sentence by looking for the correct use of capital letters, punctuation, and if the sentence ends in a complete stop, not in the middle of the sentence. A complete sentence also always contains a verb, expresses a complete idea, and makes sense when it stands alone. If one or all of these do not match up then the sentence is a fragment.
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