14. A system comprising: an electronic data store configured to store content synchronization information, wherein the content synchronization information indicates a plurality of words that occur in both an item of textual content and in an item of audio content; and a computing device, comprising a physical processor, that is in communication with the electronic data store, the computing device configured to: select a word, from the plurality of words, for modified audible presentation; cause a textual presentation of one or more words, from the plurality of words, that precede the word selected for modified audible presentation; prompt a user to input the word selected for modified audible presentation; receive a response to the prompt as one of audio input or textual input; determine that the response includes the word selected for modified audible presentation; and subsequent to determining that the response includes the word selected for modified audible presentation, cause audible presentation of one or more words, from the plurality of words, that follow the word selected for modified audible presentation.
20. The system of claim 14 , wherein the computing device is configured to cause modified audible presentation of the word selected for modified audible presentation by audibly presenting the word with an incorrect pronunciation.