Pack adverbs are provided in this article. The words listed here are commonly found along with the verb pack in sentences. This reference page helps answer the question what are some adverbs that describe or modify the verb PACK.
carefully, closely
lightly, really
simply, tightly
Hope this word list had the pack adverb you were looking for. In addition to adverbs used with pack, other example verb adverb pairings can be found on this site.
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