RU Type 
stem + "ru"
stem ends in "i" or "e"

U type 
stem + buffer consonant + "u"
buffer consonants are "s" "k" "g" "t" "r" "n" "m" "b" or nothing

Irregular 
"suru" and "kuru"

Semi-Irregular
"iku" "aru" and honorific verbs ending in "-aru"

           Non-past         Past
Affirm     hana-s-u         hana-s-ita
Negative   hana-s-anai      
 
Polite     hana-s-imasu
P.Neg      hana-s-imasen

TE form    hana-s-ite







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