While Chinese
culture does not approach tea as ritualistically as
Japanese, there are none-the-less rituals associated with it.
When tea is served (which is usually the case when you eat out), each person is given a small teacup and the whole table gets a teapot; it is rare for one individual to have their own individual tea.
These teacups are continually topped up -- you don't just fill them in when the cup is empty; you top up someone's cup, even when it is almost full. People take turns to pour the tea for everyone else; though it's usually the less senior diners who do the pouring.
When someone pours you tea, it's usual to tap on the table twice next to your cup with your forefinger and index finger. This is based on a legend that there was once a king who went out into the populace to live with the people incognito. To fit in, he poured tea for his personal servant. The personal servant did not know how to thank the king, he wanted to bow to him, of course, but this was impossible and would reveal the disguise. So the king accepted the "double tap" as a substitute for bowing.
When the teapot is empty, the lid is taken off and rested on the handle. This is an indication to the restaurant's staff that they need more tea. At this point, they'll either take it away and fill it up with hot water, or sometimes come around with big pots full of hot water and pour the hot water into the teapot.
Huge amounts of tea are consumed in this way. It's not unusual for a table of four people to go through five pots.