From Paul Brians’ book Common Errors in English Usage (to which he allows no-cost access on the Washington State University website), here is an English usage worksheet on the noun graffiti. The mild irony here, of course, is that graffiti is an Italian noun, and a plural at that; the singular is graffito. In any case, the worksheet consists of a relatively short (four sentences) reading passage with ten modified cloze exercises.
This is not a vital area of usage, but the worksheet does supply students with an opportunity to do usage analysis, which is more or less the point of these worksheets–and the meet the standard (see “English Usage” in the About Posts & Texts page on this blog, which you can reach by clicking on that title on the masthead of the site) that animated them in the first place.
If you find typos in this document, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.