【文章內(nèi)容簡(jiǎn)介】 to an increase in childhood obesity, which can have a greater negative impact on a child39。s life than the risk of being injured due to being active. ? How do we go from being a society that does not encourage its children to walk independently to being one that does? Parents must face their own disfort with letting go. Brussoni, an expert who researches children39。s outdoor and risky play, said We want to move parents from focusing solely on protecting their child to building trust in their child’s abilities and strategies to support their child’s skills in navigating the streetscape. Schools can play a role by encouraging children to walk to school. Brussoni offers additional suggestions: They should promote a culture that walking to school is the norm, help educate parents on why this is important, and consider closing the streets around the school to cars before and after school. Parents might do well to put themselves in their children39。s shoes. As adults, we know how good a morning walk feels to start off a day or to end one. Walking energizes us and cheers us up, and it can do the same for children. As we go through this pandemic that has shaken up all of our lives, it39。s a good time to practice new routines and establish new habits. Walking to school is a great place to start.28. What can we infer about kids’ usual way of going to school? A. They walk to school alone. B. They are driven to school. C. They ride bikes to school. D. They are led to school by teachers. 29. What does Brussoni suggest parents do in paragraph 3? A. Focus on their child’s safety. B. Protect their child against injury. C. Believe their child’s abilities. D. Strike traffic rules into their child’s heart.30. What does the underlined word “They” in paragraph 4 refer to? A. Schools. B. Societies. C. Governments. D. Children.31. What is the author’s purpose of writing the text? A. To illustrate the roles of parents and schools. B. To advise parents to have kids walk to school. C. To promote a way of establishing a new routine. D. To encourage kids to form a good habit.D Israeli researchers say they have created the world39。s first threedimensional, or 3Dprinted heart using a patient39。s own cells. They described the experiment as a major medical breakthrough. Tal Dvir, the lead researcher on the project, said in a statement that it was the first time that human cells had been used with 3D printing technology to successfully create a whole heart. Dvir added that the printed heart contains blood vessels which are needed to pump blood. The development marks a step forward for 3D printing in the medical field. The researchers took samples of fatty tissue from patients. This material was then used to develop “ink” for the 3D printing process. First, the researchers created patches of tissue from the patient’s own cells. Later, they used that same process to create a small version of a whole heart. Using the patient’s own cells is important to reduce the risk that the body’s system to fight infection will reject a transplanted organ. The goal, the researchers said, is to treat heart disease. The World Health Organization reports that heart disease is by far the leading cause of death worldwide. For patients with severe heart disease, a heart transplant is currently the main treatment available. The researchers hope their invention can help ease the demand for heart transplant donors. Dvir says that the newlycreated heart represents great progress. However, more research and development is needed to produce a fully operating, transplantable organ. One of the biggest challenges for the engineering team will be finding a way to create a humansized heart. Dvir said his team planned to transplant heart models designed for animals, possibly within the next year. He added that, for human use, “simpler organs” will likely be produced before hearts. “Maybe, in ten years, there will be organ printers in the finest hospitals around the world,” Dvir said. He hopes such methods will be used “routinely” to produce organs in the future.32. Why should patients’ own cells are used to create a 3D heart? A. To avoid being rejected. B. To make it suitable to print. C. To fight infection. D. To build up immune system.33. What is the research intended for? A. To adopt pri