| nom. | gen. | dat. | acc. | inst. | prep. |
Forming the instrumental plural, just like the dative and prepositional plurals, is extremely easy! These 3 plurals are all formed in a similar way. Instead of worrying about gender, we only have to worry about soft and hard endings. This means that only two endings are possible: –ами and –ями.
| Purpose |
To learn the purpose of this case, click here.
| Formation |
Forming this case is a piece of cake! Only two endings are possible.

| Hard endings (-ами) |
| а, о or consonant | книга (book) стол (table) окно (window) | книгами – столами – окнами – |
So, as you can see, if the word ends in a hard vowel such as: а or о, or a consonant, the ending will be ами.
| Soft endings (-ями) |
| e, й, or a soft sign | здание (building) музей (museum) постель (bed) | зданиями – музеями – постелями – |
So, as you can see, if the word ends in a soft vowel such as e, я, the soft consonant й, or a soft sign, the ending will be ями.

Please keep the spelling rules in mind!
| вещь (thing) | вещами – |
| солнце (sun) | солнцами – |
If a noun has an irregular plural in the nominative case, it maintains it in other plural forms.
| дом [дома] (house) лес [леса] (forest) … друг [друзья] (friend) брат [братья] (brother) … время [времена] (time) имя [имена] (name) … дочь [дочери] (daughter) мать [матери] (mother) | домами – лесами – … друзьями – братьями – … временами – именами – … дочерями – матерями – |
And there you have it! Another case-related post has been published.
I think all we have left is the accusative plural.
Hope you enjoyed the lesson. See you soon!