Learn Hardcore Italian: Ho molti libri da leggere.

In Italian molto behaves like an adjective or adverb, so it must agree in gender and number with the noun it modifies. Here libri is masculine plural, so you use molti (masculine plural form) rather than molto (masculine singular).

Can I put molti after libri, as in “Ho libri molti da leggere”?

No, standard Italian places quantity adjectives (like molti, pochi, tanti) before the noun. Saying “Ho libri molti da leggere” sounds unnatural. You always say molti libri.

Why isn’t there an article before molti libri (no “dei” or “i”)?

Because molti is an indefinite adjective that already conveys “many of.” You don’t need dei. If you added i (the), you’d be saying “I have the many books to read,” which changes the meaning to a specific set you and your listener already know about.

What does da leggere mean exactly? Why use da + infinitive?

The construction da + infinitive expresses something “to be done” or “pending.” So da leggere literally means “to be read.” It highlights that those books still need reading, without explicitly using a modal verb like “must.”

Is da leggere the same as saying che devo leggere (“that I must read”)?

They’re similar but not identical:

da leggere simply states the books are waiting to be read (neutral tone).
che devo leggere adds your personal obligation or decision: “that I have to read.” Use da leggere for general pending tasks and devo leggere when you want to stress your obligation.

Could I say Ci sono molti libri da leggere instead of Ho molti libri da leggere?

Yes, but with a nuance:

Ho molti libri da leggere focuses on your personal possession: these books are yours.
Ci sono molti libri da leggere states existence: “There are many books to read” (maybe in the library, store, or anywhere), not necessarily yours.

Why do we use avere here? Can’t I say possiedo molti libri da leggere?

Both are correct, but everyday Italian uses avere for simple possession (“I have”). Possedere (“to own”) is more formal or technical. Saying Ho molti libri sounds natural in conversation.