原题Long thought to be essentially immobile, adult Chelonia mydas, that addle to sea turtle shells, have been observed to shift slightly in position over time—a phenomenon that has been attributed to the barnacles’ passive displacement by water currents. ______ a research team found that adult C. mydas moved toward the heads of their sea turtle hosts and thus against the prevailing water flow, behavior consistent with self-initiated locomotion.Which choice completes the text with the most logical transition?A. Confirming this hypothesis,B. Undermining this explanation,C. Drawing a similar conclusion,D. Contrary to this phenomenon,解析答案：B这道题的核心在于理清前后文的逻辑关系。前文指出，海龟壳上的藤壶位置缓慢移动被归因于“水流被动冲刷藤壶”这一解释；而后文研究团队发现，藤壶是朝着海龟宿主头部移动，且逆着水流方向，这是“自主移动”的行为，显然与前文“被动冲刷”的解释相悖。A选项“证实这一假设”与后文矛盾；C选项“得出相似结论”不符合逻辑，后文结论与前文相反；D选项“与这一现象相反”表述错误，后文是反驳对现象的解释，而非现象本身；B选项“推翻这一解释”精准体现了前后文的转折否定关系，是唯一符合逻辑的过渡。*SAT备考语法真题难题完整版PDF+v：P15502147668
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难题：语境逻辑与过渡词衔接
SAT备考语法真题难题解析
原题In Annie Dillard's Pilgrim at Tinker Creek, where early on, the author marvels at a single goldfish's delicate fins but later laughs when imagining a horde of goldfish eating their own eggs—Dillard struggles to reconcile the complicated juxtapositions of the natural world. ______ nature's mesmerizing intricacy and pitiless harshness prove inextricably linked for Dillard, like "two branches of the same creek."Which choice completes the text with the most logical transition?A. Ultimately,B. To that end,C. Hence,D. Moreover,解析答案：A首先分析文本逻辑：前文描述了Dillard在书中对自然世界复杂对立现象的纠结与思考，后文则总结出自然的精妙与残酷在她眼中密不可分的结论。B选项“为此”，通常用于表示为了达成某个目的，后文并非前文的目的，排除；C选项“因此”，侧重因果推导，前文是思考过程，后文是最终感悟，并非严格的因果关系，排除；D选项“此外”，表并列补充，后文是总结而非补充，排除；A选项“最终”，恰如其分地引出对前文思考的总结性结论，完美契合语境逻辑。*SAT备考语法真题难题完整版PDF+v：P15502147668
03
难题：标准英语标点与插入语用法
SAT备考语法真题难题解析
原题Between June 22 and July 2 each year, particles shed by comet 7P/Pons-Winnecke enter Earth's atmosphere at a velocity of 18 kilometers per second. Relatively few of these particles are likely to reach Earth's ______ since the meteoroids' compression of the air surrounding them causes the vast majority to burn up in the mesosphere, producing the June Boötid meteor shower.Which choice completes the text so that it conforms to the conventions of Standard English?A. surface; however,B. surface, howeverC. surface; however,D. surface. However,解析答案：C这道题考查分号与插入语however的用法规范。首先，前后两个分句均为完整的独立句，且存在转折关系。分号（;）可用于连接两个语义紧密的独立句，而句号（.）后首字母需大写，但此处“however”作为插入语嵌在转折句中，用分号连接更符合语法简洁性要求，因此排除B、D选项；其次，插入语“however”前后需用逗号与句子其他成分隔开，即“however,”的形式，A选项缺少分号后的逗号，格式错误；C选项“surface; however,”既满足分号连接独立句的规则，又符合插入语的标点使用规范，是唯一符合标准英语语法的选项。*SAT备考语法真题难题完整版PDF+v：P15502147668以上就是这三道SAT语法真题难题的完整解析，是不是感觉瞬间理清了思路？更多同类考点的拓展内容已整理成SAT备考语法真题难题PDF资料。这份PDF资料针对性极强，聚焦语法高频难题与易混淆考点，无论是考前冲刺查漏补缺，还是日常刷题积累，都能帮你精准突破语法瓶颈。如果你正在准备SAT备考，或者不确定孩子的学习路径是否正确，可以来上海蒲公英教育预约一次免费的SAT水平测试和试听课，让专业的老师帮你找到最适合的SAT备考方案。
