On jest trochę zazdrosny o mojego przyjaciela.

to be

Breakdown of On jest trochę zazdrosny o mojego przyjaciela.

• on: he
• mój: my
• przyjaciel: the friend

Questions & Answers about On jest trochę zazdrosny o mojego przyjaciela.

Why do we need jest here? Could we just say On trochę zazdrosny o mojego przyjaciela?

In standard Polish, you normally keep the verb być (here: jest) in sentences like this:

• On jest trochę zazdrosny. – He is a bit jealous.

You can sometimes hear On trochę zazdrosny in very colloquial speech, but it sounds more like a short, telegraphic comment or spoken emphasis, not a neutral full sentence.

More natural options are:

• On jest trochę zazdrosny o mojego przyjaciela. – neutral.
• Jest trochę zazdrosny o mojego przyjaciela. – also very natural; dropping on is fine when it’s clear who you’re talking about.

So:

• Dropping on = often OK.
• Dropping jest = possible in casual speech, but less standard; keep jest in learner Polish.

Why is it zazdrosny o and not some other preposition (like na)?

The adjective zazdrosny simply takes the preposition o in Polish:

• zazdrosny o kogoś / o coś – jealous of someone / of something

This is just how the language works; you have to memorize it as a fixed pattern, like “afraid of” in English.

Compare with other emotion-preposition patterns:

• zły na kogoś – angry at someone
• dumny z kogoś – proud of someone
• pewny czegoś – sure of something