Help in examples ...

["riderofgiraffes" <lojban@solipsys.co.uk>]

I've been trying to explain to someone why it is when discussing 
lojban that "standard" linguistic terms such as "noun", "complex noun 
phrase" and "verb", etc., don't suffice. 
 
I've pointed out that the clarity and unity provided by a single 
concept of "predicate with arguments" makes it simpler, and that 
introducing "noun", "verb", etc. simply makes the situation more 
complex, but it doesn't work with her mindset. 
 
Please can someone provide me with a few examples where a sumti 
cannot be passed of as "just a complex sort of noun"? 
 
Thanks.