pages file is missing its index.xml file?

all the "pages" files which i have created on my computer recently are saying that they have the file is missing its "index.xml"

im freaking out because i have two uni assignemnts due and both files aren't opeing!

help!

i have opened the content of the file.. and all other places are telling me there should be a file called index.zip, in there and to rename it as .pages or to copy off and re open it, or to rename it as zip.xml and try again...

nothing is working