Pages with duplicate tags

Hi wordpress team,

At Google webmaster tools I checked my HTML improvements tab and it turned out that I have some duplicate tags. How can I resolve this or get rid of these tags? My blog: http://www.musicarrangerspage.com and here is the excel file from google webmasters: https://dl.dropbox.com/u/67198234/www-musicarrangerspage-com_20120829T135309Z_HTMLImprovements_Duplicate_title_tags.rar
I’m relatively still a newbie when it comes to duplicate tags.

With friendly greetings,
whitelight