How do we get students to see the benefit of understanding the parts of speech and applying their knowledge? The part of speech of a word is determined by the way the word is used in a sentence. This worksheet lists nine words that could be adverbs or prepositions. It just depends on how they are used in the sentence. It asks students to write one sentence using each word as an adverb and one sentence using each word as a preposition. The first word - on - is completed as an example. Be sure to download the preview to see how the worksheet is set up. The stars are replaced with words on the purchased download.