Which one?

Huh?

Which bank?

I don’t know, does it matter?

Not really, but why did you say the bank if it doesn’t matter?

I don’t know, that’s just what we say.

Have you ever found yourself saying that you’re going to go to a bank? Of course not, that’d be weird, wouldn’t it? But if you think about it, it doesn’t make sense if you’re from a large town or city. When we say the bank, it sounds like we’re referring to a single, specific bank that the listener knows. Now this is fine if you’re in a smallish town with only one bank. But if you live somewhere with more than one bank it sounds strange to say the bank, as though there were only one bank. We do the same with other phrases like…

I’m going to the pub.

I’m going to the shops (particularly in England).

I’m going to the cinema.

This is something that learners can find confusing. They’re trained to get used to the idea that the refers to one specific thing, usually known to both the speaker and listener, and a/an refers to a non-specific example of something general, e.g.

I’d like to get a dog.

I’m scared of the dog next door.

But saying I’m going to the bank goes against that general rule, as we’re not specifying which bank. What’s the reason for this apparent little linguistic oddity then? I think it’s simple enough. Most large towns will have many pubs, cities, and cinemas, but in the past, when modern English was developing and people were mostly living in small villages, there would usually only be one pub, or bank, or eventually, cinema, and people got into the habit of using the. Lots of the villages became towns, and some of them became cities, but a phrase that sounds good has a way of surviving long past the logical time for it to disappear.

So if you’re a sophisticated city slicker, next time you’re going to the pub or the cinema, take a moment to appreciate the options you have!