One of the IU narrators is difficult to understand. The narrator in Querying Data from Database speaks too quickly and does not enunciate well enough in almost all the videos he narrated. Querying Data from Database may not be the best example, but if one were to review all of his videos and compare them to the other narrators, you will better understand what I am complaining about. I often had to replay his videos multiple times, yet rarely replayed anyone else's.