I just read this in the Wikipedia article on the Mattaponi River and it really tickled me. If only all language were so rational!
- The Mat River and the Ta River join in Spotsylvania County to form the Matta River;
- The Po River and the Ni River join in Caroline County to form the Poni River;
- The Matta River and the Poni River join in Caroline County to form the Mattaponi River.
In Japanese, these aren't noun suffixes but number suffixes, known as counters or classifiers. You don't say, "*ninjin ga san" [three carrots], but rather, "ninjin ga sanbon" [three-cylinder-shaped carrots].
Mass nouns behave in a similar way in English: you don't say "*three breads", but rather, "three loaves of bread". Also, "head of cattle", "slices of toast", "sheets of paper", "items of cutlery", etc.
In Navajo, the classifiers are verb stems.