扫描二维码，直接登录
题库 / GMATAdvanced-SC-12
Since the 1930s aircraft manufacturers have tried to build airplanes with frictionless wings, shaped so smoothly and perfectly that the air passing over them would not become turbulent.
wings, shaped so smoothly and perfectly
wings, wings so smooth and so perfectly shaped
wings that are shaped so smooth and perfect
wings, shaped in such a smooth and perfect manner
wings, wings having been shaped smoothly and perfectly so
还没有题目讲解（毕出老师会陆续发布对官方考题的解读，请保持关注）。
C 选项里：wings that are shaped so smooth and perfect ，里面smooth 和 perfect 都是用来修饰shaped 而不是wings 的。副词修饰动词，smooth 可以做形容词和副词，但是perfect只做形容词，错了。应用smooth and perfectly 更合适
since后面是一个句子，可是从句不是也 应该是一个句子嘛？为什么5个选项从句都没有谓语动词，还是我理解错了？！？
Since the 1930s 是一个时间状语吧
登录 或 注册 后可以参加讨论
我的理解是第二个wings才是真正主语，因为前半句话是since打头，所以主语应该在逗号后面。ps：smooth自己就是副词。
兄弟，我又来了😓…
这个since是个介词，它加了时间名词the 1930s后作状语，所以逗号前面是个主谓宾完整的句子，其实逗号后面应该是同位语从句，解释wings的属性的；
另外“smooth自己就是副词”一说我也不太认同，查了下个人觉得较为权威的OELD词典，它作副词时的解释是In a way that is without difficulties，偏向于解释为“顺利地，没什么阻碍地”（例the course of true love never did run smooth），这里用来修饰shaped不太合适吧。所以这里smooth就是形容词，意为“光滑的”修饰wings，而perfectly是副词修饰shaped，两者加起来perfectly shaped又变成noun modifier，和smooth并列修饰wings，来解释其属性。
来了老弟~谢谢解释，让我看到另一种分析方法。我之前一直认为同位语从句，就应该是另一个同样意思的名词开头解释前面的名词，或者v-ed/v-ing解释这种，重复前面的名词写一个句子算是主句。看过你的解释后再看这个题，发现第二个wings如果是主语的话，主句是不完整的。
登录 或 注册 后可以参加讨论
主句结构是： manufacturers（主语） have tried to build（谓语） airplanes （宾语）with frictionless wings（宾语补充），理论上如果后面要用, shaped...的话，Shaped的动作发出者要么是是manufacturers,要么是airplanes，然而题目是想说wings, 所以一定要加wings或That从句以免引起歧义，只能选BC，而C里面perfect要用副词形式
同意
登录 或 注册 后可以参加讨论
After coma, “wings” is required because pronoun “them” is present towards the end of the sentence.
For pronoun “them” a clear antecedent is needed. This antecedent will be “wings” which must be placed after coma.
Hence, A, C, and D are incorrect. Moreover in C, instead of adverbs (smoothly and perfectly) adjectives (smooth and perfect) have been used.
Furthermore in D, “smooth and perfect manner” mean “smoothly and perfectly” hence, D is wordier by one word than the sentence was required.
同位语的四种形式：名词以及短语（有时有逗号分开）、动名词短语（有逗号分开）、不定式短语（有时有逗号隔开）、形容词及其短语（有逗号隔开）
B选项中 后一个wings表示同位语，其后为定语从句，省略主语和谓语。整体用于解释wings的属性
smooth形容翼型的顺滑，perfectly形容be shaped，表明形状被设计的很完美
主要是因为不能说smoothly shaped. B是同位语从句
A and E: shaped SMOOTHLY
smoothly means performed WITHOUT DIFFICULTY.
Thus, shaped smoothly means shaped WITHOUT DIFFICULTY, implying that the process of shaping the wings is easy.
Not the intended meaning.
The intended meaning is not that the shaping PROCESS is smooth but that the WINGS themselves are SMOOTH.
Eliminate A and E.
C: are shaped so smooth and perfect
Here, smooth and perfect (two adjectives) seem to modify are shaped (a verb).
An adjective cannot modify a verb.
An adjective must serve to modify a NOUN.
Eliminate C.
D: shaped in such a smooth and perfect manner
Like A and E, this option implies that the MANNER of shaping the wings is EASY.
Not the intended meaning.
The intended meaning is not that the shaping MANNER is smooth but that the WINGS themselves are SMOOTH.
Eliminate D.
OA: Since the 1930's aircraft manufacturers have tried to build airplanes with frictionless wings, wings so smooth and so perfectly shaped that the air passing over them would not become turbulent.
The portion in green is an example of a RESUMPTIVE MODIFIER.
A resumptive modifier:
-- repeats a key word in the sentence
-- conveys additional information about that key word
-- often includes a that-clause
-- usually appears at the end of a sentence
In the OA, the resumptive modifier makes it clear that so smooth and so perfectly shaped refers only to the WINGS, not to the entire airplane.
smooth 修饰wings，不修饰shape这个动词，所以……
smooth可以做一个副词
再者xx shaped和shaped XX这里都是修饰shaped的，都要用副词，没有说前面副词后面就是其他形式的
AD错误在于这个想用同位语修饰wings属性，但是只有分词修饰，那应该是修饰主句主语的，所以一定要有一个wings
A：wings, shaped so smoothly and perfectly。shaped so smoothly and perfectly没有说明是修饰 wings 还是 airplanes。shaped smoothly被包含于shaped perfectly，语义重复，应该换成 smooth.
C sth are shaped so smoothly...
个人理解：
A和D里边的shaped...有歧义，可以看做是wings的定语，也可以看做是独立主格结构做状语，动作的承受着变成了manufacturer，有歧义，排除。
C里边应该用副词，that are shaped so smooth and perfectly, 排除。
E里边过去完成时不能变成动名词修饰名词，having been done/having done看到就可以排除。
C项 这里的smooth和perfect是修饰shaped的，应该用副词形式
A项 非划线部分的them指代对象不明，像B这样补出一个明确的同位语就能够避免指代对象不明
shaped so smoothly 不能直接修饰前面的wings shaped 的逻辑注意是前面airplane ，manufactured 。所以要重新重述 wings
smooth可以做副词， perfect是形容词， smooth and perfectly
B：wings的同位语。后半句wings后面的是做宾语从句吧？
如果不加wings同位语会有歧义
perfectly 修饰shape, smooth修饰wings
smooth可以做副词， perfect是形容词， smooth and perfectly
smooth可以做副词， perfect是形容词， smooth and perfectly