O livro publicado em 1950 é interessante.

The book published in 1950 is interesting.

Breakdown of O livro publicado em 1950 é interessante.

• ser: to be
• em: in
• o livro: the book
• interessante: interesting
• 1950: 1950
• publicado: published

Questions & Answers about O livro publicado em 1950 é interessante.

Why do we need the article O before livro? Could we just say Livro publicado em 1950 é interessante?

In European Portuguese, singular countable nouns almost always need a definite or indefinite article, even where English can omit it.

• O livro = the book
• Um livro = a book

So:

• O livro publicado em 1950 é interessante.
  = The book published in 1950 is interesting.

If you say Livro publicado em 1950 é interessante, it sounds incomplete or like a note heading/title, not a normal sentence. In standard speech and writing, you need the article: O livro.

What exactly is publicado here? Is it a verb or an adjective?

Publicado is the past participle of the verb publicar (to publish), but here it is used as a kind of adjective.

The fuller “underlying” sentence would be:

• O livro que foi publicado em 1950 é interessante.
  The book that was published in 1950 is interesting.

This gets “reduced” by dropping que foi, leaving:

• O livro publicado em 1950 é interessante.

So publicado agrees with livro (masculine, singular) and functions like an adjective describing livro: the book (which was) published in 1950.

Why doesn’t the sentence use que (that/which)? Why not O livro que foi publicado em 1950 é interessante?

You can say:

• O livro que foi publicado em 1950 é interessante.

It’s perfectly correct and clear. However, Portuguese very often omits que foi in this type of sentence and uses the past participle directly:

• O livro publicado em 1950…

This is a common, more compact way to form a relative clause, especially in written language. The meaning is the same; the version without que foi is simply more concise:

• With que foi: a full relative clause.
• Without que foi: a reduced relative clause using the participle.

Why is publicado after livro and not before it, like in English (published book)?

In Portuguese, most descriptive adjectives—and participles used like adjectives—normally come after the noun:

• um livro interessante (an interesting book)
• um livro antigo (an old book)
• um livro publicado em 1950

Putting them before the noun is possible but usually adds emphasis, expressiveness, or changes nuance, and doesn’t work naturally with all adjectives.

So livro publicado is the standard word order. Saying publicado livro would be wrong in this context.

How does gender and number agreement work with publicado here?

Publicado must agree with the noun it describes in both gender (masculine/feminine) and number (singular/plural).

In the original sentence:

• o livro → masculine singular
• → publicado (masculine singular)

Other examples:

• a revista publicada em 1950
  (the magazine published in 1950) → feminine singular → publicada
• os livros publicados em 1950
  (the books published in 1950) → masculine plural → publicados
• as revistas publicadas em 1950
  (the magazines published in 1950) → feminine plural → publicadas

So the endings are: -o, -a, -os, -as to match the noun.

Why is it em 1950 and not no 1950?

With years, Portuguese normally uses em without any article:

• em 1950
• em 2020
• em 1999

No = em + o (in + the), but we don’t use an article with bare years, so no 1950 is incorrect.

If you explicitly say “the year 1950”, then you can use no:

• no ano de 1950
  (in the year 1950)

But with just the year, it’s simply em 1950.

Can em 1950 be moved to a different position in the sentence?

Yes, you have some flexibility with adverbial phrases like em 1950. For example:

• O livro publicado em 1950 é interessante. (most neutral)
• O livro, publicado em 1950, é interessante. (with commas; see below)
• Em 1950, o livro publicado é interessante. (awkward as a general statement; sounds like focusing on that specific year)
• O livro é interessante, publicado em 1950. (feels like an afterthought; not the most natural form)

The version you were given—O livro publicado em 1950 é interessante—is the cleanest and most typical way to say this.

What’s the difference between O livro publicado em 1950 é interessante and O livro foi publicado em 1950?

They focus on different things:

1. O livro publicado em 1950 é interessante.

   • Main information: the book is interesting.
   • Extra information: it was published in 1950.
   • Structure: [noun + descriptive phrase] + é interessante.

2. O livro foi publicado em 1950.

   • Main information: it was published in 1950 (the event/time of publication).
   • It says nothing about whether it’s interesting or not.
   • Structure: foi publicado is the passive verb.

So the first sentence describes a quality of the book; the second reports a past event about the book.

Why is it é interessante and not está interessante?

In Portuguese, ser and estar are both “to be” but they behave differently:

• ser (→ é) is used for permanent or inherent characteristics.
• estar (→ está) is used for temporary states or conditions.

Here, interessante describes a general, inherent quality of the book. So we use ser:

• O livro é interessante.

Using está interessante would imply something more temporary or contextual (for example, “right now it’s interesting”, or in contrast to before), and sounds strange for a book’s overall quality.

Could I say O livro era interessante or O livro foi interessante? What changes?

Yes, both are grammatically correct, but the meaning shifts to the past:

• O livro é interessante.
  The book is interesting. (now, in general)

• O livro era interessante.
  The book was interesting.
  → Imperfect past: describing a state in the past, often with some background idea, or in contrast to now (maybe it no longer seems interesting to you).

• O livro foi interessante.
  The book was interesting.
  → Simple past (perfect): usually referring to a specific event or experience that is now over (e.g., a lecture, a talk).
  For books, foi interessante is less natural; you would typically use era or é.

What’s the difference between O livro publicado em 1950 é interessante and O livro, publicado em 1950, é interessante with commas?

The commas change the nuance, like in English:

• O livro publicado em 1950 é interessante.
  → The phrase publicado em 1950 is restrictive: it identifies which book you’re talking about.
  The book (that was) published in 1950 is interesting — as opposed to other books.

• O livro, publicado em 1950, é interessante.
  → The phrase publicado em 1950 is non-restrictive: extra information about the book, not needed to identify it.
  The book, which was published in 1950, is interesting.

In many real contexts the difference is subtle, but grammatically this is the contrast the commas indicate.

How do I make the sentence plural?

You need to make the article, noun, participle, and verb all agree in the plural:

• O livro publicado em 1950 é interessante.
  (The book … is interesting.)

Plural:

• Os livros publicados em 1950 são interessantes.
  (The books published in 1950 are interesting.)

Changes:

• o → os
• livro → livros
• publicado → publicados
• é → são
• interessante → interessantes

How is livro pronounced in European Portuguese? Is it similar to Spanish libro?

In European Portuguese:

• livro → roughly [ˈli.vɾu]

Key points:

• li- is like lee in “leaf”.
• -vr-: the v is like English v, and the r is a tap [ɾ], similar to the single r in Spanish “pero”, or the quick t in American English “water” (when pronounced “wadder”).
• Final -o is a short, fairly closed sound, not as strong as English “oh”, a bit more like the u in British “put” but with rounded lips.

Compared with Spanish libro:

• The b vs v are slightly different.
• The r in European Portuguese here is also a tap, so fairly similar to Spanish r in this position.

Is there anything special about how publicado is pronounced in European Portuguese?

Yes, a couple of typical EP features:

• publicado → roughly [publiˈkaðu]
  • Stress on -ca-: pu-bli-CA-do.
  • Final -do: the d can soften and the o is often quite weak, sounding closer to -du.
  • All vowels are fairly short and clear.

Syllable breakdown: pu-bli-ca-do with the main stress on ca.