duplicate title tags with wordpress !

Hello

today i see in my google webmaster tools duplicate title tags
i dont install any gallery plugin
i copy one of them and try it with default wordpress theme
and give me seam home page title !!!

any idea how fix this? like redirect this pages to home page directly

the problem like this .. try to insert in your wordpress site in address and see

/index.php?mpage=about
/index.php?mpage=contact
/index.php?mpage=gallery&gallery_img=0
/index.php?mpage=gallery&gallery_img=1
/index.php?mpage=gallery&gallery_img=2
/index.php?mpage=gallery&gallery_img=3
/index.php?mpage=gallery&gallery_img=4
/index.php?mpage=gallery
/index.php?mpage=home
/index.php?mpage=news&item=0
/index.php?mpage=news&item=1
/index.php?mpage=news&item=2
/index.php?mpage=news&item=3
/index.php?mpage=news&item=4
/index.php?mpage=news&item=5
/index.php?mpage=news&item=6
/index.php?mpage=news&item=7
/index.php?mpage=news&item=8
/index.php?mpage=news&item=9
/index.php?mpage=news
/index.php?mpage=services
/index.php?mpage=typography

thanks

It might be caused by not setting up your wordpress seo plugin correctly. Generally try to do something like Page Name - Blog Title. I recommend Yoast SEO.