11.In the dead of winter,we don't typically think about spending time outdoors,but according to many physicians we should.The sun is our greatest source of a vitamin that is essential for good health-Vitamin D.
This important vitamin strengthens bones and teeth and is linked to the prevention of heart disease,cancer and many other life-threatening diseases.The recommended daily requirement is 400-600 International Units (IU).In summer,people with dark brown eyes and darker skin turn sunlight from just 15 minutes outside without sunscreen into adequate amounts of Vitamin D.
Even during winter,just a 10-minute walk midday can keep the body's Vitamin D at healthy levels.During brief winter walks,we receive the greatest benefits when we wear no sunscreen and expose as much skin to the sun as possible.
Vitamin D can also be obtained from foods.Salmon is one of the best sources of the Vitamin.Egg yolks(蛋黃),cheese,mushrooms and some animals organs contain smaller quantities of it.
To attract consumers,food companies add Vitamin D to some of their milk products.The practice of putting the Vitamin into milk began in the 1930s.At that time,many children were suffering from rickets,an illness that is caused by a Vitamin D deficiency(不足).It made the children's bones soft and weak.Adding Vitamin D to milk helped to solve the problem,and it has been available ever since.
For people who still need more Vitamin D,there is another option:take Vitamin D supplements(補充).These products are widely sold in stores.However,anyone considering taking supplements should consult a physician first.
28.During the winter months,peopleC.
A.a(chǎn)ren't able to meet their deadlines
B.often don't dress warmly enough
C.generally like to remain indoors
D.leave lots of work for others to do
29.According to the text,Vitamin DA.
A.can be obtained by being exposed to the sun
B.can be used to cure life-threatening diseases
C.can be mainly found in some milk products
D.can make the children's bones soft and weak
30.Why is salmon mentioned in this article?B
A.It's seldom prepared in.the correct way.
B.It's a useful addition to a person's diet.
C.It has a huge impact on the environment.
D.Its advantages have been exaggerated.
31.The main purpose of this article isA.
A.to introduce a valuable nutrient
B.to advertise Vitamin D supplements
C.to note risks associated with a nutrien
tD.to explain how a nutrient was discovered.
分析 本文屬于說明文閱讀,作者通過這篇文章主要向我們描述了一種寶貴的營養(yǎng)維生素D的作用以及獲取維生素D的方式.
解答 28.C.細節(jié)理解題.根據(jù)第一段In the dead of winter,we don't typically think about spending time outdoors,but according to many physicians we should可知冬天的時候,人們喜歡待在屋里;故選C.
29.A.細節(jié)理解題.根據(jù)第一段The sun is our greatest source of a vitamin that is essential for good health-Vitamin D可知維生素D可通過曬太陽獲得;故選A.
30.B.推理判斷題.根據(jù)第四段Salmon is one of the best sources of the Vitamin.Egg yolks(蛋黃),cheese,mushrooms and some animals organs contain smaller quantities of it可知鮭魚是一種有益的膳食;故選B.
31.A.推理判斷題.根據(jù)最后一段For people who still need more Vitamin D,there is another option:take Vitamin D supplements(補充).These products are widely sold in stores.However,anyone considering taking supplements should consult a physician first可知本文的主要目的是介紹一種寶貴的營養(yǎng);故選A.
點評 考察學生的細節(jié)理解和推理判斷能力,做細節(jié)理解題時一定要找到文章中的原句,和題干進行比較,再做出正確的選擇.在做推理判斷題不要以個人的主觀想象代替文章的事實,要根據(jù)文章事實進行合乎邏輯的推理判斷.