hmm. just reviewed the r' winder prefixes and suffixes w/ chana and she pretty much remembered them all.
so the trouble seems to be that she is having difficulty going from theoretical to practical. seeing it in the actual words while she's translating everything else is causing trouble.
i would recommend (though will i actually do it?) that i scout out the pasuk in advance, review those prefixes and suffixes right before the lesson, and see if that helps.