El libro es muy pesado.

Breakdown of El libro es muy pesado.

ser
to be
el libro
the book
muy
very
pesado
heavy

Questions & Answers about El libro es muy pesado.

Why does the sentence use ser (“es”) and not estar (“está”)?
In Spanish, ser describes inherent or permanent characteristics, while estar is for temporary states or locations. Weight is seen as an inherent property of an object, so you say El libro es muy pesado. You’d only use estar if you meant it had become heavy under unusual circumstances (e.g., “El libro está más pesado hoy” would sound odd anyway; you’d normally stick with ser).
Why is muy placed before pesado?
Muy is an adverb of degree (very) and in Spanish it comes directly before the adjective it modifies. So you say muy pesado, not pesado muy.
Does pesado change form for gender and number?

Yes. As an adjective, pesado agrees with the noun:

  • Masculine singular: pesado (el libro pesado)
  • Feminine singular: pesada (la caja pesada)
  • Masculine plural: pesados (los libros pesados)
  • Feminine plural: pesadas (las cajas pesadas)
Can pesado have non-literal meanings?
Absolutely. Besides “heavy,” pesado can mean “boring” or “tedious” when referring to a person or activity (Eres muy pesado = You’re so annoying/bordensome). Context tells you if it’s literal weight or a figurative sense.
How would you ask “How much does the book weigh?” in Spanish?

You’d use the verb pesar. The question is
¿Cuánto pesa el libro?
Literally, “How much does the book weigh?”

Why do we include the definite article el before libro?
In Spanish you generally use articles before nouns, even in general statements. So instead of “Book is very heavy,” you say “El libro es muy pesado.” Omitting the article would sound unnatural or change the nuance.
What’s the opposite of pesado in this context?

The direct opposite is ligero (light). So you could say
El libro es muy ligero
to mean “The book is very light.”

Where is the stress in the word pesado, and does it need an accent mark?
Pesado is stressed on the penultimate syllable: pe-SA-do. Because it’s a word ending in a vowel and the stress is on the second-to-last syllable, no written accent is needed.
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