How to get files off of dropbox once in ipad

i have a dropbox im using to sync several pdfs across my pcs and macs and ios. so far it rocks and everything works. The only problem is Im running out of the free space they give you. since i technically dont need to sync every single one of em is there a way to move them or copy them out of my dropbox onto another location on the ipad. i have goodreader and was able to open files that were in dropbox with goodreader but i dont know if its just reading the file from its original location or if it copys it to goodreader. i could really use some help with this.