首页
登录
职称英语
Sunlight is a great source of vitamin D in most of the world. Yet a (an)【C1】
Sunlight is a great source of vitamin D in most of the world. Yet a (an)【C1】
游客
2023-07-19
75
管理
问题
Sunlight is a great source of vitamin D in most of the world. Yet a (an)【C1】______number of experts think that many people aren’t getting enough vitamin D—【C2】______those who work and play indoors.
It’s long been known that vitamin D is【C3】______for strong bones. Research in the last several years has shown that low levels of vitamin D may increase the risk of heart【C4】______in men and deaths from some cancers. But new research suggests that it also protects against a wide【C5】______of diseases. Low levels of vitamin D have also been【C6】______with various forms of cancer and high blood pressure, stroke,【C7】______illness etc. The strongest source,【C8】______far, is ultraviolet (紫外线) B rays from the sun, which【C9】______a form of cholesterol (胆固醇) into vitamin D in the skin. But UVB rays【C10】______greatly depending on cloud cover, time of year and time of day. Dark-skinned and elderly people don’t【C11】______vitamin D from the sun as【C12】______as younger, fair-skinned people. UVB rays also don’t【C13】______glass or sunscreen with a factor of 8 or more. It’s difficult to get much vitamin D through diet. Few foods【C14】______it naturally. It’s widely【C15】______that most people need some supplemental vitamin D—the question is, how much? Current U. S. guidelines, issued in 1997,【C16】______for 200 international units from birth through age 50. The National Osteoporosis Foundation【C17】______adults over age 50 to get at least 800 to 1,000 IUs to【C18】______against fractures (骨折).
But as some experts research carry【C19】______the experiment, they worry that if people take too much vitamin D, it might act as a poison. Also, skin doctors warn people to be careful with sun【C20】______because of the risk of skin cancer. [br] 【C18】
选项
A、guard
B、take
C、set
D、count
答案
A
解析
动词词组辨义题。前面提到“全美骨质疏松症基金会建议50岁以上的成年人每天至少补充800一1000IU的维生素”,目的是“防止发生骨折”,guard against“防止,提防”符合题意。take against“反对,不喜欢”;set against“反对,使对立,使平衡”;count against“不利于”,均不符合文意,故排除。
转载请注明原文地址:http://tihaiku.com/zcyy/2849830.html
相关试题推荐
Mygrandma’swrinkles______inthestrongsunlight,thoughshedidn’tadmittha
[originaltext]W:Goodeveningandwelcometothisweek’sBusinessWorld.Itpro
Manshouldnotexploitthenaturalresources______(以牺牲其他物种为代价).atthecostofsa
[originaltext]Extremelyhotweatheriscommoninmanypartsoftheworld.A
[originaltext]Extremelyhotweatheriscommoninmanypartsoftheworld.A
SunlightisagreatsourceofvitaminDinmostoftheworld.Yeta(an)【C1】
SunlightisagreatsourceofvitaminDinmostoftheworld.Yeta(an)【C1】
SunlightisagreatsourceofvitaminDinmostoftheworld.Yeta(an)【C1】
SunlightisagreatsourceofvitaminDinmostoftheworld.Yeta(an)【C1】
SunlightisagreatsourceofvitaminDinmostoftheworld.Yeta(an)【C1】
随机试题
Businesseslargeand【C1】______,nowrealizethatphysicalworkspaceinfluenc
小李是一个小公司的职员,收入不高,再加上妻子有病,孩子上学,家庭经济状况不好,虽
根据《建设工程质量管理条例》,设计人员需要( )。[2021年回忆版]A.委托
阅读以下教学片段,回答问题。 (1)教师用幻灯片展示出关于“物质与意识关系”的
文明施工应当在( )过程实施。A、土方开挖至主体封顶施工阶段 B、项目部进场
A.水解 B.氧化 C.异构化 D.聚合 E.脱羧维生素C的主要降解途径
农村居民在哪方面的人均消费支出比重一直大于城镇居民?() A.食品、交通
社会主义经济和资本主义经济都是以社会化大生产为基础的商品经济。( )[中国农业
治疗心力衰竭时,可抑制心肌重构和心肌纤维化的治疗药物不包括A.血管紧张素转换酶抑
某工艺服装厂承接一万套服装来料加工合同,加工期两年,成品全部返销日本,合同规定,
最新回复
(
0
)