听力原文
How to keep your eyesight sharp
１. Boost your beta carotene1) intake. Eat lots of oranges and yellow fruits and vegetables such as spinach.
２. Eat other carotenoids too. Beta carotene is only one of more than ５００members of the carotenoid family. A study also suggests that carotenoids found in green leafy vegetables（such as broccoli2） and kale3)）may help prevent vision loss.
３. Stay active. A study found that people who bicycled four times a week for ４０minutes had a ２０percent drop in eye pressure.
４. Block the sun. Some studies link long-term exposure to ultraviolet4) rays（UV）to cataract5) formation. To protect your eyes, wear sunglasses with a special coating that locks UV light.
５. Stop smoking. According to a study, people who smoke 35 or more cigarettes a day have a 63 percent greater risk of developing cataracts.
参考译文
如何保持敏锐的视力
１. 增加β-胡萝卜素的摄入量。 食用大量的柑橘、黄色水果和蔬菜, 如菠菜。
２. 同时摄入其他类胡萝卜素。 β-胡萝卜素在５００多个成员的类胡萝卜素属中, 只是其中一员。一项研究报告指出, 在绿叶蔬菜（如花椰菜和甘蓝菜）中发现的类胡萝卜素, 可能有助于防止视力下降。
３. 经常活动。 一项研究发现, 一星期骑自行车４次共４０分钟的人, 眼压降低２％。
４. 遮挡阳光。有些研究认为白内障的形成与眼睛长期暴露在紫外线下有关。可戴镀有防紫外线膜的太阳镜来保护眼睛。
５. 戒烟。 研究表明, 与不吸烟的人相比, 一天抽３５支烟或更多的人, 得白内障的危险高６３％。
NOTE 注释：
carotene [5kArEti:n] n. [生化]胡罗卜素
broccoli [5brCkEli] n. 椰菜
kale [keil, kel] n. 羽衣甘蓝
ultraviolet [5QltrE5vaiElit] adj. 紫外线的, 紫外的
cataract [5kAtErAkt] n. 白内障
