Drain adverbs are provided in this article. The words listed here are commonly found along with the verb drain in sentences. This reference page helps answer the question what are some adverbs that describe or modify the verb DRAIN.
completely, directly
eventually, properly
quickly, slowly
thoroughly
Hope this word list had the drain adverb you were looking for. In addition to adverbs used with drain, other example verb adverb pairings can be found on this site.
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