Noun. Genitive Plural

The genitive plural is formed from the stem of the partitive singular.
When the partitive singular ends with a vowel, the genitive plural ends with -de.
poeg, poja, poega > poegade

When the partitive singular ends with -d, the genitive plural usually ends with -de.
maa, maa, maad > maade

When the partitive singular ends with -t, the genitive plural ends with -te / -de.
Genitive plural ending with -te:
valge, valge, valget > valgete
raamat, raamatu, raamatut > raamatute
noor, noore, noort > noorte
saabas, saapa, saabast > saabaste

Genitive plural ending with -de:
roosa, roosa, roosat > roosade
kõne, kõne, kõnet > kõnede
tütar, tütre, tütart > tütarde

 Exceptions:
1) The genitive plural is formed in an exceptional way from the genitive singular in the word võti (and other words declined analogously).
kaste, kastme, kastet > kastmete
võti, võtme, võtit > võtmete

2) When the partitive singular ends with -kku, also the short form can be used in the genitive plural.
õnnelik, õnneliku, õnnelikku > õnnelikkude ~ õnnelike

3) Words ending with a vowel in the partitive singular end with -te in the genitive plural:
poiss, poisi, poissi > poiste
koer, koera, koera > koerte

 Connections between Cases

The singular and plural cases (except the short form of the illative singular) have the same endings starting from the illative.
The nominative plural is formed from the stem of the genitive singular by adding the plural marker -d.
hammas, hamba, hammast > hambad

The genitive plural is formed from the stem of the partitive singular with the markers -de or -te.
hammas, hamba, hammast > hammaste

All other plural cases (except the partitive) are formed by adding the appropriate case ending to the genitive plural form.
noorte tütarde > noortesse tütardesse, noortel tütardel

The attribute does not agree with the headword in the last four cases.
E.g. haigete hammaste > haigetesse hammastesse, haigetel hammastel
but: haigete hammasteni, haigete hammastena, haigete hammasteta, haigete hammastega

The -de plural can be formed with all nouns.

Connections between Cases I

 Connections between Cases II