Season 3——manhattan 54 （已点评）

sanlingjie

54. Geologists once thought that the molten rock known as lava was an underground remnant of Earth's earliest days, sporadically erupting through volcanoes, but they now know that it is continuously created by the heat of the radioactivity deep inside the planet.

A   was an underground remnant of Earth's earliest days, sporadically erupting

B   had been an underground remnant of Earth's earliest days and sporadically erupted

C   was an underground remnant of Earth's earliest days, which sporadically erupted

D   would be an underground remnant of Earth's earliest days that sporadically erupted

E   was an underground remnant of Earth's earliest days, having sporadically erupted

The original sentence does not contain any errors. The verb clause "was an underground remnant of Earth's earliest days" is correct in tense (simple past "was") and number (singular "molten rock" paired with singular "was").  Moreover, the modifier "sporadically erupting through volcanoes" correctly modifies the preceding clause.

(A)CORRECT.  This choice is correct as it repeats the original sentence.

(B) This choice unnecessarily and incorrectly changes the simple past "was" to the past perfect "had been," which is used only when describing the earlier of two past actions. Moreover, the use of "and" here equates the geologists' false understanding of lava with the fact that it sometimes erupts through volcanoes.

(C) This choice improperly uses the relative pronoun "which" to modify "Earth's earliest days" instead of "molten rock known as lava."

(D) This choice incorrectly changes the simple past "was" to the conditional "would be." Moreover, the use of "that" implies that eruption through volcanoes was part of what the geologists erroneously believed about lava.

(E) In this choice, "having sporadically erupted" incorrectly places this modifier in the past tense, implying that lava no longer erupts through volcanoes.

注意：which一般是就近指代，还有就是注意情态动词的取舍，没有的不要随便加，有的不要随便去掉，总之不要改变句子的愿意，尽量。

balapupu

Geologists once thought that the molten rock known as lava was an underground remnant of Earth's earliest days, sporadically erupting through volcanoes, but they now know that it is continuously created by the heat of the radioactivity deep inside the planet.

A   was an underground remnant of Earth's earliest days, sporadically erupting-->R

B   had been an underground remnant of Earth's earliest days and sporadically erupted-->过去完成时木有意义。且ed形式木有Ing形式更好的表示状态。。

C   was an underground remnant of Earth's earliest days, which sporadically erupted-->which有指代days的歧义.

D   would be an underground remnant of Earth's earliest days that sporadically erupted-->不是表示对将来的推测，语气错。

E   was an underground remnant of Earth's earliest days, having sporadically erupted-->having 冗余

laiweizhou

同样也是是纠结在AC
但最后觉得选C
诚然 主系表结构，可以对宾语进行描绘和解释。 好像OG 有一题是 选protecting. 但A选项相对比较复杂。erupting 的逻辑主语真的不是很清晰，而且好像在此句中做伴随发生不是很好。

C中which 可以修饰不可拆分的整体underground remnant of Earth's earliest days。 另外在此句中用which地非限制性定语从句做修饰，比ing做伴随或者解释要好。

corneliaflower

54. Geologists once thought that the molten rock known as lava was an underground remnant of Earth's earliest days, sporadically erupting through volcanoes, but they now know that it is continuously created by the heat of the radioactivity deep inside the planet.

A   was an underground remnant of Earth's earliest days, sporadically erupting

B   had been an underground remnant of Earth's earliest days and sporadically erupted

C   was an underground remnant of Earth's earliest days, which sporadically erupted

D   would be an underground remnant of Earth's earliest days that sporadically erupted

E   was an underground remnant of Earth's earliest days, having sporadically erupted

选A
首先根据一般过去时态排除BD
其次having sporadically erupted 错误
AC纠结了一下
underground remnant of Earth's earliest days中得of 是表示从属还是时间呢？ 觉得还是从属关系
所以which sporadically erupted紧邻修饰days错

winghyy

选A
1.根据 G once thought that...but they know that it is, 对比用一般过去时was，排除BD
2. C, which 错误修饰，会引起歧义以为修饰an underground remnant
3 . E.having sporadically erupted 错误，不需要用完成时，sporadically erupt 是一种现象

mahaofei001

纠结在AC中，就是因为没有搞懂什么样子的修饰在GMAT中是最好的问题。
A中逗号后的ing形式确实有对句子主语的修饰作用，然而此时它被置于一个that从句中了，所以它所修饰的主语应该还是the molten rock。
doudoulong1302说的那两个题，我也看了看，Neuroscientists, having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, are now drawing solid conclusions about how the human brain grows and how babies acquire language.是说的这个吗？感觉这个和本题讲的还是有出入的，具体说不上来，等待讲解中。

C的话，which却是很歧义的指代days。两个相对比看，还是A的表述更好些。

最后要指出的是1#中指出的那种错误修饰确实存在，要小心啊！

xeyyxzty

54. Geologists once thought that the molten rock known as lava was an underground remnant of Earth's earliest days, sporadically erupting through volcanoes, but they now know that it is continuously created by the heat of the radioactivity deep inside the planet.

A   was an underground remnant of Earth's earliest days, sporadically erupting
--right（排除法~~~）
B   had been an underground remnant of Earth's earliest days and sporadically erupted--erupted through volcanoes解释an underground remnant，并列后不对~~~还有had been 不知道对不对
C   was an underground remnant of Earth's earliest days, which sporadically erupted
--which指代days，错
D   would be an underground remnant of Earth's earliest days that sporadically erupted
--would be~X
E   was an underground remnant of Earth's earliest days, having sporadically erupted
--having done~不对吧

Jane412

选A
B：had been和erupted时态不对
C：which不是修饰紧邻的名词吗，那这里就不对了。。。
D：would时态不对
E：having erupted不对。好像prep里说，having done的这种形式要改掉

jofre

54. Geologists once thought that the molten rock known as lava was an underground remnant of Earth's earliest days, sporadically erupting through volcanoes, but they now know that it is continuously created by the heat of the radioactivity deep inside the planet.
A   was an underground remnant of Earth's earliest days, sporadically erupting
B   had been an underground remnant of Earth's earliest days and sporadically erupted
C   was an underground remnant of Earth's earliest days, which sporadically erupted
D   would be an underground remnant of Earth's earliest days that sporadically erupted
E   was an underground remnant of Earth's earliest days, having sporadically erupted

选C
1. Geologists once thought使用一般过去式，that从句表示一种认知，应该跟随主句时态使用一般过去式，BD选项错；
2. 后半部分的短语erupt用分词形式的话，逻辑上看逻辑主语应该是underground remnan，但语法上逻辑主语是Geologists或the molten rock，AE选项错；
3. having sporadically erupted表示动作在the molten rock was an underground remnant之前发生，而实际上underground remnan不时（sporadically）会喷发出来，而非过去特定某时间发生，E选项错；
4. be动词一般不与动词形成并列结构，B选项错
5. that从句前不加逗号，表示限制性定语从句，但是从逻辑上看，这里应该是非限制性定语从句，选项D错

zealdin

选A

sporadically erupting 起修饰作用。所以用ing形式

但是有点纠结于B的 ....and ... erupted.. 感觉该选项想表达一个parallel的意思，但是前面的had been时态又不正确

C。。which错，指代不明

D。。that 指代不明，且would时态错，这是一个虽然是推测的，但是已经存在的现象，而非即将发生的事

E。。having错