Just a few questions:

Why do vowels get lengthened when suffixes are added (fa 'tree' -> fa'k
'trees')? Would this be considered umlaut, or was fa originally fa', but the
vowel got shortened only in the singular form, and the long vowel was
preserved in the plural form?

What are the vowel harmony rules?

Why have enni and inni collapsed 2pl and 3pl (esznek, isznak)? (Altho that
"collapsing" might just be an illusion of my notes.) What are some other /n/
> /s/ verbs?

Are there any other bipersonal suffixes like -lek?


P.S. How do the modern languages compare with PFU? What was PFU's phonemic
inventory? How many cases did it have? What sort of changes did Finnish,
Hungarian, Estonian etc. go through from PFU? Any information is