Learn Spanish (Latin America): Los estudiantes están ocupados en la oficina.

This lesson is all about the difference between ser and estar. We use estar (here, están) for two main things: temporary states and locations. This sentence actually has both! The students are temporarily busy (ocupados), and they are located in the office (en la oficina).

Why is there an -s at the end of ocupados?

In Spanish, describing words (adjectives) must match the noun they describe. Because los estudiantes is plural (more than one), the word for busy must also be plural, making it ocupados.

Estudiantes doesn't end in -o or -a. How do we know its gender?

Many words for people that end in -e (like estudiante) use the exact same spelling for both masculine and feminine. You have to look at the little word before it to know! The masculine plural los tells us this is a masculine group, which is also used for a mixed group of male and female students.

Can en mean both "in" and "at"?

Yes! The word en is very versatile. It can mean "in", "on", or "at". Depending on the context, en la oficina could perfectly translate to either "in the office" or "at the office".