Tea is important in many cultures. Tea is not a British drink. Actually, I think it's a Chinese drink. But there is something different, something special about the way the British make tea and the way the British think about tea.
Whenever the English feel awkward or uncomfortable in a social situation, They make tea. It's like a special rule. When in doubt, put the kettle on. Now these four words are possibly the most important words in the English language.
The kettle is a piece of equipment(设备) in every British kitchen. It's the thing that makes hot water. It boils(烧开) water. So when a British person says "I'll put the kettle on", this always means "I'm going to make tea". When visitors arrive in our home, we say "I'll put the kettle on". When we are in a difficult social situation, when we don't know what to say, when the conversation becomes silent, we say "I'll put the kettle on". After a bad accident or when people are injured and in shock, tea is always needed. So tea is still believed by British people to have some kind of magical power.
For British people, whatever the problem is, what you need is a nice cup of tea.