Learn Farsi: هجده ماشین در خیابان است. - There are eighteen cars in the street.

In Farsi, nouns that come immediately after a number are always kept in their singular form. You do not add a plural ending. It translates literally as "eighteen car".

Why does the sentence end with است (is) instead of a plural verb like "are"?

In Farsi, inanimate objects (things that are not alive, like cars) usually take a singular verb, even when there are multiple of them. Since ماشین is an inanimate object, the sentence uses the singular verb است.

Where is the word for "there" (as in "there are") in this Farsi sentence?

Farsi doesn't use a filler word like "there" to say that something exists in a location. You just say what the thing is, where it is, and end with the "to be" verb. Literally, this sentence translates to "Eighteen car in street is."

In English, we usually say "on the street." Why does Farsi use در (in)?

Prepositions rarely match up perfectly between languages. While در generally means "in", Farsi uses it for streets where English speakers might prefer "on". You will see در خیابان used for both "in the street" and "on the street".