A. Visiting the parents regularly

B. Moving the kitchen table regularly

C. Secretly giving and receiving the shirt

D. Often tapping something to the bottom of the table

28. What is the important reason for the author’s valuing the shirt so much?

A. That her daughter needs it in art class

B. That it is from her dead Mom

C. That it is still in decent shape though faded

D. That it symbolizes mother’s love

C

Tipping isn’t a big part of British culture, unlike in North America, where waiters and waitresses are paid below minimum wage. Tips are usually appreciated, but offering a tip of some services can cause confusion.

In casual restaurants, where yopay for your order at a counter but food is brought to your table, tipping is uncommon. Yoare welcome to leave a pound or two if yowish. In restaurants where yoplace your order with a waiter or a waitress and receive your food and bill at your table, it’s customary to tip around 10 percent. In some restaurants, a service charge may be added to the bill automatically, typically 10 or 12.5 percent. In this case, yodon’t need to add a further tip. When yopay by credit card, the machine may ask if yowant to add a tip. Check your bill to see if a service charge has already been added before paying—if so yodon’t need to add a tip on the machine. Yocan request the service charge be removed from your bill if yoare unhappy with the service. In some cases a restaurant may print “service not included” on the bill or menu. This is a request for a tip. You’re not forced to offer anything, but 10 percent would be normal in this situation. Tipping in cafes and fast food restaurant is not expected.

If youse a taxi, round the fare up to the nearest pound shown on the meter. On a journey from or to the airport in a booked minicab yomight wish to trip 2 or 3 pounds if the driver helps with your bags.

Be sure to check a country’s tipping culture before yostart your tip. For more information, visit TripAdvisor.com.

29. According to the text, ________ in British culture.

A. it is necessary to tip if yoare served in cafes

B. it is confusing to tip if yoreceive your bill at your table

C. it is customary to tip if “service not included” is printed on the bill

D. it is compulsory to tip even if the service is unsatisfying in some restaurants

30. When yopay by credit card, _________.

A. the service charge can be added on the machine

B. the service charge must have been included in the bill automatically

C. the service charge can’t be refused

D. the service charge needn’t be checked before yopay

31. If the British taxi meter shows 58.4 pounds, yoare expected to pay ________.

A. 58.4 pounds B. 59 pounds

C. 61 pounds D. 64 pounds

32. What is the best title for the text?

A. Introduction of TripAdvisor.com B. Occasions for Tipping

C. Advice on Tipping in Restaurants D. British Ways to Tipping

D

In a study published in the U. S. journal Science, researchers from the Chinese Academy of Agricultural Sciences(CAAS) and the University of Florida identified the chemical combinations and genetic recipe for better tomato flavor(味道).

“In recent years, consumers often complain that the modern tomato is less flavorful than it once was” said co-principal researcher Sanwen Huang. “Our results provide a practical road map for breeding tomato varieties with better flavor.”

For the study, a 170-person consumer group was created to evaluate 160 tomatoes representing 101 varieties, based on qualities such as “overall liking” and “flavor degree”. The results pointed to dozens of chemical compounds of interest, and further research using a statistical model discovered 33 flavor compounds connected with consumer liking, such as glucose(葡萄糖). The reason why modern tomatoes don’t taste good anymore is that a total of 13 of these flavor-associated compounds “were significantly reduced in modern varieties,” their paper wrote. Moreover, the researchers found that smaller fruit tended to have greater sugar content, suggesting that “selection for more sizable tomatoes has cost sweetness and flavor”.

Based on this knowledge, Huang and Professor Harry Klee of the University of Florida studied the whole genomes of 398 varieties of tomato, identifying about 250 positions of genes on a chromosome(染色体), which controlled tomato flavor.

“We’re just fixing what has been damaged over the last half century to push them back to where they were a century ago,” said Klee in a statement. “We can make the supermarket tomato taste noticeably better.” Klee said new tomato varieties with better flavor could be ready in three to four years. In addition, “the genes and pathways identified here in the tomato almost certainly point to pathways worth researching for improvement of flavor quality in other fruit crops,” they wrote.

33. According to the text, the study_______.

A. was carried out just through a survey

B. was conducted by Chinese researchers themselves

C. was completely focused on the genes of different tomatoes