If you intend to spend much time in a Spanish speaking country, then you MUST learn the proper use of the verbs prestar, devolver, pedir, deber. Let's begin with learning about the Spanish words for borrow and lend.

prestar - to lend

Si quieres, te presto mis cd's.
If you want, I lend you my cd's.

¿Me prestas tu grapadora?
Can you lend me your stapler?

Dice que le presta su cacharro.
She says that she can lend you her old car.

Allí prestan dinero.
They lend money there.

pedir prestado - to borrow

El señor que le pidió a usted dinero prestado vino ayer.
The man who borrowed money from you came yesterday.

Ustedes no tuvieron necesidad de pedir dinero prestado al banco.
You all had no need to borrow money from the bank.

Now, let's review the Spanish words for returning and owing.

devolver - to return something

Ellos devuelven sus libros.
They return their books.

deber - to owe
Note: The meaning changes when deber is followed by an infinitive.

Tú debes mucho dinero.
You owe a lot of money.

No me debes nada.
You don't owe me anything.