All About Adverbs: How Likely?Gear up for a little grammar practice. Introduce your second grader to the wonderful world of adverbs with this worksheet that tells all about adverbs of probability—adverbs that describe how likely something is. He'll flex his grammar and comprehension muscles as he reads each sentence, then picks the probability adverb that best completes each one. Get more adverb help with the rest of the All About Adverbs series.