Learn Farsi: پسر بی‌قرار در اتاق انتظار ایستاده است. - The restless boy is standing in the waiting room.

For posture and condition verbs like standing or sitting, Farsi uses the present perfect tense to express a continuous state in the present. The phrase istade ast literally means he has assumed a standing position and is still in it, which is how Farsi says he is standing.

Does otagh-e entezar mean the word entezar is an adjective?

No, entezar is a noun that means expectation or waiting. The invisible ezafe vowel connects the two nouns together to mean room of waiting. This is the standard way to form compound concepts like waiting room in Farsi.

What does the prefix bi- do in the word bi-gharar?

The prefix bi- means without or -less. Since gharar means peace, stability, or rest, adding the prefix creates bi-gharar, which translates to without rest or restless.

Why is there an invisible ezafe after pesar but not after bi-gharar?

The ezafe vowel connects a noun to its modifiers, so we say pesar-e bi-gharar to link the boy to the adjective restless. We do not put an ezafe after the adjective here because it is the end of that noun phrase, and the sentence moves on to the preposition dar.