How to use strings with variables in codeigniter's language files?
I have the same problem and do it simply by using,
echo sprintf($this->lang->line('somekey'),'XYZ');//load language library before useRead sprintf()
you can use codeigniter i18n with PHP .sprintf() to achieve what you want. load up the codeigniter non-variable strings (with those format stuff), then pass it on to .sprintf() for formatting and assignment of values. it should replace the %s part.
it's similar to this question. .sprintf() works like .printf(), only that it returns the string rather than printing it.