The verb dar means to give:
Nunca uso este abrigo, si quieres, te lo doy –
I never use this coat, if you want I will
give it to you
¿Me das tu número de teléfono? – Can you
give me your phone number?
The verb regalar also means to give but it
is used when we are talking about a birthday or another occasion for making a
gift:
Vale, te regalo esta bolsa – Well, I´ll give
you this bag
No sé qué voy a regalar a mi abuela – I don´t know
which gift can I make for my grandmother
Papá, ¿me regalas una bicicleta?
– Daddy, can you buy me a bicycle?
Dejar can be translated as to loan, to lend.
In Latin America you should better use prestar with
the same meaning:
Te dejo mi abrigo, pero luego me lo devuelves, ¿vale? (= Te presto mi abrigo) – I will lend you my coat, but then you will return it to me, ok?
¿Me dejas 20 euros? = ¿Me prestas 20 euros? – Will you lend me 20 euros?
Devolver means to return, to give back:
Voy a devolver este jersey: no me gusta – I am going to give back this sweater, I don´t like it