Astounded adverbs are provided in this article. The words listed here are commonly found along with the verb astounded in sentences. This reference page helps answer the question what are some adverbs that describe or modify the verb ASTOUNDED.
absolutely, completely
fairly, perfectly
simply, utterly
Hope this word list had the astounded adverb you were looking for. In addition to adverbs used with astounded, other example verb adverb pairings can be found on this site.
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