Lesson 23
Memorize New Vocabulary
In Lesson 21 you learned how to use the Instrumental case for nouns. This lesson will focus on how to use the instrumental case for adjectives.
Just as nouns take different endings when used alongside the verb “byc”, so do adjectives. Below are the endings for adjectives in the instrumental case.
| Adjective Gender | Adjective Ending |
| Masculine | -(i)m / -(y)m |
| Feminine | -ą |
| Neuter | -(i)m / -(y)m |

Apply It To Sentence Structure
We will now go through the steps of how to change the endings of an adjective for the Instrumental case.
| For Masculine Adjectives | For Feminine Adjectives |
Step 1: grzeczny – heavy | Step 1: sympatyczna - nice |
Step 2: Add -(i)m / -(y)m ending: grzecznym | Step 2: Change –a ending into –ą ending: sympatyczną |
Step 3: Ja jestem grzecznym synem. I am a well behaved son. | Step 3: Ja jestem sympatyczną babcią. I am a nice grandma. |
As you have probably noticed, for masculine and neuter adjectives our table includes -(i)m / -(y)m endings. Let’s look at this in a little bit more detail.
Why are the vowels –i and –y in brackets?
The vowels in brackets mean that the vowel may or may not be added. The vowel –i or –y is not added when such a vowel already exists at the end of the adjective.
Examples:
Ciężki – Ciężkim
Ładny – Ładnym
How do I know when to change the ending into –im and when to –ym?
The ending –im will appear only when the last consonant is g, k or ń. In these cases the vowel –i will soften the consonant in order to make it easier to pronounce. (This rule also applies to nouns and other parts of speech)
Examples:
Ciężki – Ciężkim
Brzydki urzędnik – ugly clerk
Brzydkim urzędnikiem – ugly clerk (instrumental)
Try it for yourself!
Say the below phrases out loud (do not worry about extra vocabulary, this exercise is targeted at pronunciation):
1. Lekkym ołówkem (light pencil) | 1. Niebieskym pociągem (blue train) |
OR | OR |
2. Lekkim ołówkiem | 2. Niebieskim pociągiem |
Which phrases are easier to say? Yes, lekkim ołówkiem and niebieskim pociągiem are easier! They also sound better and more proficient. Try to remember this rule.

Practice it!
Base Adjective | Adjective in Instrumental Case |
niebieski | |
duża | |
ciepła | |
czerwone | |
biedny | |
cienki | |
grube | |
mała | |
ładna | |
przystojny | |
*Click here for answer key*
Lesson 22 Lesson 24