The permanent employees get a salary every month, but because I am temporary I get my wages in cash every week. I don’t get a lot of money, because I am a waiter—but the customers often give me tips. I am friendly to my customers because I hope they will be generous. Because I am temporary, I only get ￡6 an hour, and I don't get money when I don't work. I want to go to Italy to see my parents. But I haven't got enough money and I don't get holiday pay. It's a pity. Also, I don't get sick pay when I am ill. But I can work extra hours. I often do overtime at the weekend if the restaurant is busy. At Christmas the boss gives us extra money—a bonus.

“Tip”is closest in meaning （意义）to（）.