Learn Farsi: آن کارگر اثاثیه را آورده است.

It is made of two parts: the past participle آورده (brought) and the third-person singular copula است (is). To make a past participle, take the past stem of آوردن (to bring), which is آورد, and add ه. Together with است, it translates to "has brought".

Why is است written as a separate word here?

In the present perfect tense, the third-person singular (he/she/it) uses the full word است. This is an exception! For all other persons, we use short endings that attach to the past participle, such as آورده‌ام (I have brought) or آورده‌ای (you have brought).

Why is the word را placed after اثاثیه?

The word را is the specific direct object marker. Because the worker brought a specific thing ("the" furniture, rather than furniture in general), we must put را right after اثاثیه to show it receives the action of the verb.

Is the word اثاثیه singular or plural?

اثاثیه is a collective noun meaning "furniture" or "furnishings". Just like the word "furniture" in English, it represents a group of items but is treated grammatically as a single unit, which is why it does not have a standard plural ending like ها.