الكتاب من القرن الماضي.

Because this is a present-tense nominal sentence in Arabic. In Modern Standard Arabic, the verb to be is usually omitted in the present.

So:

الكتاب من القرن الماضي
literally: the book from the past century

but naturally: The book is from the last/past century.

If you wanted a past-tense version, Arabic would usually include a form of كان: كان الكتاب من القرن الماضي = The book was from the last century.

Here is the basic breakdown:

• الكتاب = the book
• من = from
• القرن = the century
• الماضي = past / last

So the structure is:

الكتاب + من القرن الماضي
= The book + from the past century

Here من means from, but in a broad sense. It does not mean physical movement only. It can also show origin in time, place, material, and more.

In this sentence, it tells you the book belongs to or comes from a certain time period:

من القرن الماضي = from the last century

So it is answering the idea Which period is the book from?

Because Arabic adjectives normally come after the noun they describe.

So:

• القرن الماضي = the past century
• literally: the century the-past

This is different from English, where adjectives usually come before the noun:

• English: the past century
• Arabic: القرن الماضي

Because الماضي is an adjective describing القرن, and Arabic adjectives agree with the noun in definiteness.

Since القرن is definite (the century), the adjective must also be definite:

• القرن الماضي = the past century

If the noun were indefinite, the adjective would also be indefinite:

• قرن ماضٍ = a past century / a bygone century

So the repeated الـ is completely normal.

No. It is a noun + adjective phrase, not an iḍāfa.

Why?

Because الماضي is describing القرن, and it matches it like an adjective:

• both are definite
• both are masculine
• both are singular

So:

• القرن الماضي = the past century
  not
• the century of the past

That is why this is best understood as a regular noun followed by its adjective.

Because it has to agree with القرن.

The noun قرن is:

• masculine
• singular

So the adjective must also be:

• masculine
• singular

That gives:

• القرن الماضي

If the noun were feminine, the adjective would also become feminine. For example:

• السنة الماضية = the past year

So الماضية would be used with a feminine noun, but قرن is masculine, so we use الماضي.

Yes. The preposition من is followed by a noun in the genitive case.

So grammatically, القرن is governed by من. The adjective الماضي follows it and matches it.

In fully vowelled formal Arabic, this would be read with genitive marking after من. In normal unvowelled writing, learners usually just focus on the fact that من requires the following noun phrase to be genitive.

So the important pattern is:

• من + noun phrase
• من القرن الماضي = from the past century

A simple pronunciation is:

al-kitāb min al-qarn al-māḍī

In very formal reading with full case endings, you may hear:

al-kitābu min al-qarni al-māḍī

A few pronunciation notes:

• ك in كتاب is like k
• ق in قرن is a deep q sound, not the English k
• ض in الماضي is an emphatic consonant, often difficult for beginners

In this sentence, it is most naturally understood as last or past, depending on the translation style.

So:

• القرن الماضي can be translated as the last century
• or the past century

Both are natural in English here. The exact wording depends on context and translation preference, but the Arabic phrase itself is very common.

It is a prepositional phrase that gives extra information about الكتاب.

It tells us the book’s time origin or period:

• الكتاب = the topic
• من القرن الماضي = information about it

So the whole sentence is structured like:

The book + is from the last century

This is a very common Arabic pattern:

• البيت من الحجر = The house is made of stone
• هذا الرجل من مصر = This man is from Egypt
• الكتاب من القرن الماضي = The book is from the last century