在给幼儿园老师上口腔保健课时，特别强调了氟化物对儿童口腔保健的重要性，因为（  ）

为了获得高额垄断利润，垄断组织在采购原材料时多采取（   ）。

下列哪—成语的典故不是来自真实历史事件(  )

既能祛风湿，又能消骨鲠的药物是（  ）。

关于建设用地使用权，下列说法正确的是(  )。

请阅读  Passage 1,完成第  21~25小题 。

Passage 1

First two hours, now three hours-this ishow far in advance authorities are recommending people show up to catch adomestic flight, at least at some major U.S. airports with increasingly massivesecurity lines.

Americans are willing to toleratetime-consuming security procedures in return for increased safety. The crash ofEgyptAir Flight 804, which terrorists may have downed over the Mediterranean Sea,provides another tragic reminder of why. But demanding too much of airtravelers or providing too little security in return undermines public supportfor the process. And it should: Wasted time is a drag on Americans ' economicand private lives, not to mention infuriating.

Last year, the Transportation SecurityAdministration (TSA) found in a secret check that undercover investigators wereable to sneak weapons-both fake and real-past airport security nearly everytime they tried. Enhanced security measures since then, combined with a rise inairline travel due to the improving economy and low oil prices, have resultedin long waits at major airports such as Chicago ' s O ' Hare International. Itis not yet clear how much more effective airline security has become-but thelines are obvious.

Part of the issue is that the governmentdid not anticipate the steep increase in airline travel, so the TSA is nowrushing to get new screeners on the line. Part of the issue is that airportshave only so much room for screening lanes. Another factor may be that morepeople are trying to overpack their carry-on bags to avoid checked-baggagefees, though the airlines strongly dispute this.

There is one step the TSA could take thatwould not require remodeling airports or rushing to hire: Enroll more people inthe PreCheck program. PreCheck is supposed to be a win-win for travelers andthe TSA. Passengers who pass a background check are eligible to use expectedscreening lanes. This allows the TSA to focus. on travelers who are higherrisk, saving time for everyone involved. The TSA wants to enroll 25 millionpeople in PreCheck.

Ithas not gotten anywhere close to that, and one big reason is sticker shock:Passengers must pay $85 every five years to process their background checks.Since the beginning, this price tag has been PreCheck ' s fatal flaw. Upcomingreforms might bring the price to a more reasonable level. But Congress shouldlook into doing so directly, by helping to finance PreCheck enrollment or tocut costs in other ways.

Which of the following would be the best title for the text?

患者 ，女，30岁 。因四肢关节肿痛3月，面部红斑1月，脱发10天就诊。曾自然流产3次。
为明确诊断 ，最为重要的检查项目是

建于唐贞观年间的裴氏宗祠是现存最早的宗祠，位于今（　  ）境内。（南开大学）

关于试用期的说法，正确的是（  ）。

医疗机构抗菌药物供应目录中的碳青霉烯类抗菌药物注射剂型严格控制在

齐老师带着幼儿一边有节奏地拍手，一边不断地说着《气球和皮球》的绕口令。这种游戏形式属于(    )。