In Russian, adjectives have to match the nouns they describe. This means they need to agree in three ways: gender, number, and case.

Let’s use the word "высокий," which means "tall," in the phrase "высокие деревья," meaning "tall trees."

1. Gender: The word "деревья" (trees) is neutral and plural. So, the word "высокий" changes to "высокие" to match.

2. Number: We are talking about more than one tree. That’s why the adjective has to be plural too. This is why we use "высокие."

3. Case: The phrase "высокие деревья" is in the nominative case. This means we are simply stating what the subject is.

Here are some examples:

• "В парке растут высокие деревья." (Tall trees grow in the park.)
• "Эти высокие деревья красивы." (These tall trees are beautiful.)

When we want to compare, we change the adjectives a little. Use "выше" to mean "taller" and "самый высокий" to mean "the tallest." For example:

• "Эти деревья выше." (These trees are taller.)
• "Это самые высокие деревья в парке." (These are the tallest trees in the park.)

If you remember these simple rules, you’ll be able to use adjectives in Russian correctly!