Article: According to the Institute of Russian Language of the Russian Academy of Sciences, an optional acute accent ( ) may, and sometimes should, be used to mark stress. For example, it is used to distinguish between otherwise identical words, especially when context does not make it obvious: / (lock/castle), / (worthwhile/standing), / (this is odd/this is marvelous), / (attaboy/fine young man), / (I shall learn it/I recognize it), / (to be cutting/to have cut); to indicate the proper pronunciation of uncommon words, especially personal and family names (, , , , ), and to show which is the stressed word in a sentence ( ?/ ?/ ? Was it you who ate the cookie?/Did you eat the cookie?/Was it the cookie that you ate?). Stress marks are mandatory in lexical dictionaries and books for children or Russian learners.

Now answer this question: What can optional acute accents indicate?
stress