In Finnish, -sta verbs also belong into the first group (the one that that I made here first): olla, tulla, minna, panna, surra.
In Estonian it's much more difficult:
There are some words that belong there: 'pesta'(to wash), 'kusta'(to urinate)
This means that all the forms are formed exactly the same way as I described in my first group:
- pesta: pesema, pesen; pesin; pestakse, pesti; pesnud, pestud; pestes; pesev, pestav
- kusta: kusema, kusen; kusin; kustakse, kusti; kusnud, kustud; kustes; kusev, kustav
Then there is this a bit different word 'tõusta'(to stand/get up, to rise) - it seems to be quite similar to the previous ones, but it doesn't have e in ma-infinitive. According to ÕS, 'seista' also belongs into this group, although it gets a into its stem, not e:
- ma-infinitive: tõusma, seisma
- present: tõusen, seisan - sorry, I don't know when which vowel is used
- past: tõusin, tõusid, tõusis(3rd person); seisin, seisid, seisis
- passive: tõustakse, tõusti; seistakse, seisti
- -nud/-tud: tõusnud, tõustud; seisnud, seistud
- -des: tõustes, seistes
- -v/-tav: tõusev, tõustav; seisev, seistav
Another group - ma- and da-infinitives are -stma and -sta:
'tõsta'(to lift (up)), 'osta'(to buy), 'kasta'(to water (plants), but also to dip into a liquid), 'vesta'(to tell a story; to give shape to a wooden stick with knife)
- ma-infinitive (overlong) and present (long): tõstma, tõstan; ostma, ostan; kastma, kastan; vestma, vestan
- past (overlong): tõstsin, tõstis(3rd person); ostsin, ostis; kastsin, kastis; vestsin, vestis
- passive (long): tõstetakse, tõsteti; ostetakse, osteti; kastetakse, kasteti; vestetakse, vesteti
- -nud/-tud: tõstnud, tõstetud; ostnud, ostetud; kastnud, kastetud; vestnud, vestetud
- -des: tõstes, ostes, kastes, vestes
- -v/-tav: tõstev, tõstetav; ostev, ostetav; vestev, vestetav
vowel-vowel-TA words belong also to this group, but let's look at them separately: 'saata'(to send), 'keeta'(to boil something, (to cook)), 'veeta'(as in 'aega veetma' - to spend time), 'viita'(as in 'aega viitma' - to waste time), 'niita'(to mow)
- ma-infinitive: saatma, keetma, veetma, viitma, niitma
- present: saadan, keedan, veedan, viidan, niidan
- past: saatsin, saatis(3rd person); keetsin, keetis; veetsin, veetis; viitsin, viitis; niitsin, niitis
- passive: saadetakse, saadeti; veedetakse, veedeti; viidetakse, viideti; niidetakse, niideti
- -nud/-tud: saatnud, saadetud; etc...
- -des: saates, keetes, viites, etc...
- -v/-tav: saatev, saadetav; viitev, viidetav; etc...
And one more group - -skma / -sta: 'lasta'(to let; to shoot), 'mõsta'(to wash (dialectical))
- ma-infinitive: laskma, mõskma
- present: lasen, mõsen
- past: lasin, mõsin
- passive: lastakse, lasti; mõstakse, mõsti
- -nud/-tud: lasknud, lastud; mõsknud, mõstud
- -des: lastes, mõstes
- -v/-tav: laskev, lastav; mõskev, mõstav
mõsksin, mõsksid, mõskis, mõsksime, mõsksite, mõsksid;
But laskma allows both forms:
lasksin & lasin, lasksid & lasid, laskis & lasi, lasksime & lasime, lasksite & lasite, lasksid & lasid (or like some older people say lasivad )