Thanks to everyone once again for their generosity with all the explanations and helpful ideas to remember things (legs on a cow!).

I have been working through the book "Teach Yourself Russian Grammar" and that has helped me a lot. Going back through the exercises in Rosetta Stone I'm now able to deconstruct and understand how and why the word endings are changing - slowly for now but I know it will become second nature in time.

Except I've hit a snag regarding "shoes", but I'll start a separate thread for that.

Thanks,
Lindsay