As we all know British love queues, but there is no real line-up(队列) in a bar — and the bar workers do know whose turn it is. But there still are some rules. For example, don’t speak loudly, or snap your fingers. And whatever you do, please don’t ring the bell hanging behind the counter(柜台)---this is used by the boss to tell people it’s closing time. Remember if you look too pleased and happy, the bar workers will think they have served you.
In a British bar always say “please” and try to remember the things that the British bar workers hate. For example, they don’t like people to keep others waiting when they can’t decide what to drink. They don't like people standing against the bar when there are a lot of customers waiting for service.
One tourist who spent six months interviewing 50 bosses and more than 1,000 customers said, “I cannot understand how the British are able to buy themselves a drink. But they do, and if you follow these rules you should be able to do so, too.”
Talking of tips(小费), you should never offer the bar workers a cash gratuity(现金小费). The correct behavior is to invite them to drink something. If so, they will think that their work is worthy. A cash gratuity is unfriendly and impolite.