Sigh adverbs are provided in this article. The words listed here are commonly found along with the verb sigh in sentences. This reference page helps answer the question what are some adverbs that describe or modify the verb SIGH.
deeply
heavily
sadly
softly
vainly
Hope this word list had the sigh adverb you were looking for. In addition to adverbs used with sigh, other example verb adverb pairings can be found on this site.
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