The Difference Between AS and SINCE

Since

Desde – We’ve been doing this podcast since January, 2014.

Desde entonces – I broke up with my girlfriend six months ago and I haven’t seen her since (then).

“Since” can also mean “because” – I’ll make tea, since you’re so busy.
Since I’ll be at the conference next week, I won’t be able to go to the meeting.

As

Comparison – as blind as a bat / as flat as a pancake / as cold as ice.

While (mientras, cuando) – As I was walking home I bumped into Pepito.

(Como) – He thinks of himself as a bit of a ladies’ man. / As promised, here’s the 50 euros I owe you./ As you know, the company is doing badly.

As if/though (Como si) – The very angry man shouted as if/though he were possessed with the devil!/ She’s only been working here for a week but acts as if/though she owned the place.

(in the same manner/way as – a la manera de) – Do as I say, not as I do. /I play cricket for the local team, as my father did before me.

As for (INFORMAL) = As regards (NEUTRAL) = With respect to/With regard(s) to/In regard to/In reference to/Regarding/Concerning (MORE FORMAL) – My boss is obsessed with punctuality, but as for staff welfare he doesn’t care at all.

As=Since/because (porque) – I got you some beer, as (=since/because) you don’t like wine.
I didn’t say anything as (=since/because) I didn’t want to worry you.

So, Nacho could use “since” or “as” in his example:

“Since you are doing your podcast for free, I’d like to give something away as well.”
“As you are doing your podcast for free, I’d like to give something away as well.”

*Dispones de más PODCAST en inglés publicados en los cuadernos anteriores
a los que puedes acceder directamente así como al índice de su contenido.