甲、乙两人在相距10千米的A、B两地相向而行，甲每小时走x千米，乙每小时走2x千

船舶根据航行区域的需要，应配备有关航道图、航行指南、潮汐表及（）等航行资料。

Directions: Complete the following passage by using ONE word that fits the context.

What is happiness?   小题1:  people have different ideas. Some people are rich; they think they are happy.  小题2:  people have many friends, so they feel   小题3: . Still others are happy because their lives are meaningful. Happiness attracts everyone. For children, happiness often suggests eating something good or   小题4:  with toys.   小题5:  a stamp collector, stamps bring more delight than meals. And for a scientist, a discovery or an invention rather than  小题6: else gives him greatest satisfaction. As everything exists only because of its opposite, happiness exists only when  小题7:  exists. Just as a person who does not know failure never knows success, a person, who has not experienced suffering or sadness never knows   小题8:  happiness means. Cheer up and be happy. Happiness is not far from you. It’s just around you. Try to grasp it and enjoy it.

准高速客车

E

Sweet potatoes are fat-free, high in fiber and full of the vitamins that research suggests reduce your risk of life-shortening diseases. To stay healthy, we must eat more fruits and vegetables, and sweet potatoes are a great source of beta carotene(胡萝卜素) and other carotenoids(which the body turns into vitamin A). According to a study of the diets of almost 90,000 nurses, eating about one cup a day of fruits and vegetables rich in carotenoids can cut your risk of stroke in half and reduce your risk of heart disease by 22 percent. Other research suggests beta carotene protects against breast, lung and stomach cancers.

Beta carotene is the most famous member of the carotenoids family. In face, a medium-sized sweet potato contains nearly 12mg of beta carotene(anti-aging experts usually suggest 6 to 11 mg per day). Sweet potatoes are also a low-fat source of vitamin E. Research has linked high E diets with a lower risk of heart disease. This vitamin pill in an orange jacket also packs a vitamin C punchit which has more C than apricots (a kind of fruit). Research suggests that vitamin C protects against ailments (小疾) ranging from cataracts(an eye disease) to cancer. In addition, a UCLA (University of California Los Angeles) study linked high vitamin C diets with a longer life. Recent studies have showed that antioxidant Vitamins C, E and beta carotene fight a fierce battle against free radicals (自由基），which cause cell damage and lead to various illness. Therefore, to keep fit, eat more sweet potatoes.

72. According to the text, there exists a lot of ______in sweet potatoes.

A. fiber, beta carotene, other carotenoids, Vitamin E and C

B. beta carotene, other carotenoids, fiber, Vitamin A and E

C. Vitamin A, beta carotene, fiber, Vitamin E and C

D. beta carotene, other carotenoids, Vitamin A and E

73. This text as a whole suggests that eating sweet potatoes can help______.

A. cut your risk of stroke and heart disease

B. protect against breast, lung and stomach cancers

C. protect against ailments ranging from cataracts to cancers

D. you stay healthy and reduce your risk of life-shortening diseases

74. “ This vitamin pill in an orange jacket” in the passage refers to______.

A. sweet potato     B. vitamin C pill

C. vitamin E pill    D. beta carotene

75. The best title of this passage might be______.

A. On sweet potatoes             B. The vitamin superstar

C. Beta carotene and vitamins      D. Diet and disease