Learn Spanish (Latin America): El estudiante es inteligente.

In Spanish, adjectives that end in -e, like inteligente, don't change to match gender. They stay exactly the same whether they describe a masculine noun or a feminine noun. You only change them to add an -s if the noun is plural.

How do I know if estudiante is masculine or feminine since it ends in -e?

You can tell by looking at the word right before it! Estudiante is an invariable noun, meaning it doesn't change spelling for gender. Here, the masculine article el tells us it's a male student. If it were a female student, the sentence would start with La estudiante.

Why do we use es instead of está here?

Es comes from the verb ser, which is used to describe core traits and characteristics. Since being intelligent is considered a fundamental part of the student's personality rather than a temporary mood, we use ser. You would use estar (like está) for temporary states, like feeling tired or being busy.

If I wanted to talk about multiple students, how would this sentence change?