In Russian, adjectives have to match the nouns they describe in three important ways: gender, number, and case. Let’s make it easier to understand using the example "Я вижу старый автомобиль" which means "I see an old car."

1. Noun Gender: The word "автомобиль" (car) is masculine.

2. Adjective Form: The word "старый" (old) also has to be in its masculine form so it matches with "автомобиль."

3. Case Agreement: This sentence uses a specific case called accusative. This means "автомобиль" is the object of the verb "вижу," which means "I see." For masculine nouns in this position, the adjective stays the same as it would when we are just naming things.

Summary:

• Gender: Masculine (автомобиль → старый)
• Number: Singular
• Case: Accusative

Practice examples:

• "Я вижу новый компьютер" (I see a new computer)
• "Я вижу хороший фильм" (I see a good film)

Remember to always check the noun's gender, number, and case to choose the right form of the adjective!