In America alone, tipping is now a $16 billion-a-year industry. A recent poll showed that

In America alone, tipping is now a $16 billion-a-year industry. A recent poll showed that 40% of Americans【C1】______ the practice. Tips should not exist. So【C2】______ do they？ The conventional wisdom is that tips both【C3】______ the efforts of good service and reduce uncomfortable feelings of inequality.【C4】______ according to new research from Cornell University, tipping【C5】______ serves any useful functions. The paper analyses data from 2,547 groups dining at 20 different restaurants. The【C6】______ between larger tips and better service was very【C7】______: only a tiny part of the【C8】______ in the size of the tip had anything to do with the quality of service. Customers who rated a meal as "excellent" still tipped【C9】______ between 8% and 37% of the meal price. Tipping is better explained by culture than by economics. In America, the custom【C10】______ institutionalized: it is regarded as part of the【C11】______ cost of a service. In a New York restaurant, failing to tip at least 15% could well mean【C12】______ from the waiter. Hairdressers can expect to get 15-20%, the man who【C13】______ your groceries $2. In Europe, tipping is less common; in many restaurants, discretionary tipping is being【C14】______ by a standard service charge. In many Asian countries, tipping has never really【C15】______ at all. How to【C16】______ for these national differences？ According to Michael Lynn, the Cornell papers coauthor, countries in which people are more extrovert, sociable or neurotic tend to tip more. Tipping relieves【C17】______ about being served by strangers. And, says Mr. Lynn, "in America, where people are【C18】______ and expressive, tipping is about social approval. If you tip badly people think less of you. " Icelanders,【C19】______, do not usually tip — a measure of their【C20】______, no doubt.

【C1】

A．alarm

B．like

C．despise

D．hate

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