We can actually deduce here that a sentence fragment here is: 4. Laughing and scooping up piles of snow.
A sentence fragment is actually known to be a sentence which is written without its subject or main verb. In other words, these are sentences that have their subject or main verbs missing.
Sentence fragment can occur as a result of omission of words or even as a typographical error.
We see here that "Laughing and scooping up piles of snow" is the sentence fragment among others.
Learn more about sentence fragments on https://brainly.com/question/1811078
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