Here’s a simple guide to using adjectives in the instrumental case in Russian:

1. Making Changes: Adjectives need to change endings depending on the gender and number of the nouns they describe.

   • For Masculine nouns: use -ым or -им. (For example, "хороший" becomes "хорошим")

   • For Feminine nouns: use -ой or -ей. (For example, "хорошая" becomes "хорошей")

   • For Neuter nouns: use -ым. (For example, "хорошее" becomes "хорошим")

   • For Plural nouns: use -ыми or -ими. (For example, "хорошие" becomes "хорошими")

2. How to Use It: We use the instrumental case to show who or what is involved in an action.

   • For example: "Он пишет с хорошей ручкой." (This means "He writes with a good pen.")

3. Building Sentences: You can mix adjectives with nouns or pronouns in the instrumental form.

   • For example: "Я горжусь своим другом." (This means "I am proud of my friend.")

   • Another example: "Она идет с красивым платьем." (This means "She walks with a beautiful dress.")

To get better at using these forms, try making your own sentences!