Learn Arabic (Modern Standard): قرأ المقال رقم أربعة.

In this lesson, we are focusing on bare counting numbers. When a number acts as a label or ID like "number four" rather than counting a physical quantity (like "four articles"), you use its default bare counting form. For numbers 3 to 10, this default form ends with the feminine marker taa marbuutah.

Where is the word for "he" in this sentence?

The meaning "he" is built directly into the past tense verb قرأ. In Arabic, the simplest base form of a past tense verb always represents the "he" form, so you do not need to add a separate pronoun to say "he read."

How does the phrase رقم أربعة work grammatically?

It translates exactly to "number four." Just like in English, when you want to identify a specific item by its number (such as a room, bus, or article), you simply place the word for number (رقم) right before the bare cardinal number. Notice that you do not add the prefix for "the" to the word number.

Why does the word for article (المقال) have the prefix ال attached to it?

Because he read a specific article. In Arabic, the word for "the" is the prefix ال which attaches directly to the beginning of the noun. While English often drops "the" and just says "He read article number four," Arabic keeps the noun definite because a specific article is being discussed.