From Wikigogy

I dropped the plural s from the end of exercises in this article's title because it is not needed and creating links to pages is facilitated by not using plural s in page names. This is because s can be added to the outside of a link without breaking the link but if one removes s from the end of a link that has it in the article name the link breaks -- both [[Four skill exercise]] and [[Four skill exercise]]s work as long as the page name has no plural s. This also matches the site menu style of no plural s such as in the left sidebar. So it seems best for this page. --Roger 21:21, 15 June 2006 (UTC)

for example, see the link back to this page at the top of Alternate sentence practice