To become a British citizen, you need to pass the official test, writes Jeremy Clay. That requires study. There are plenty of books around which are full of facts about our history and handy hints about etiquette.

But you'd do just as well to get hold of a copy of last night's Three In A Bed (8pm, Channel 4).

It's a guilty pleasure of a show which sees the owners of three guesthouses stay in each other's places to find the best one.

But yesterday's episode was about far more than a mere battle of the B&Bs: It was about class and taste; it was about attitudes and outlook; it was about north and south; it was about snootiness and sneeriness and our constant need to judge others to reassure ourselves where we stand in the pecking order.

In short, it was about Britain and its myriad mini-minefields of manners. Good luck with finding a way through all that, newcomers.

First up were Anita and Derek, who run a handsome guesthouse in Bury St Edmunds.

Anita is a former child actress who once appeared in a St Trinian's film. These days, she seems to have settled into the role of Hyacinth Bucket.

She's probably perfectly pleasant in real life but she came across as a snob. "I always go to a first class supermarket," she announced, regally and unnecessarily.

Anita's house is from the 1950s, but has been cleverly tarted up to look like a Regency-era home.

Award yourself extra points for Britishness if you found yourself wondering if her own background had been as cunningly disguised.

Next were Jayne and Keith, who have a B&B in Whitby. Jane collects ornamental pigs. Feel free to admire them or turn up your nose. Both are correct.

Jayne took everyone on a trip to her favourite shop; the place where she stocks up on her pigs. "It's a Northern gift shop," sniffed Anna, owner of the final B&B on the show.

Did you catch that, citizenship students? The harmless-looking term Northern can be used pejoratively.

Down in Canterbury, Anna and her pun-loving bloke John run Arthouse, a happy-go-lucky sort of place dotted with modern art, where you have to fix your own breakfast.

Anita and Jayne, united by a British suspicion of artiness, formed an uneasy alliance of disdain.

In the end, Anita and Derek won. How? By getting the biggest cut of the cash. Each stay ends with payment time, in which the owners say how much the room costs and the guests hand over what they think it's actually worth.

That would be a straightforward transaction in near enough anywhere else in the world. Here, of course, it's a festival of crippling awkwardness.

So, did you squirm? Congratulations, you've passed. You're British. You may now commence grumbling.