Geysers are formed when subterranean igneous pressure

Leading to eruptions and so marked c.. can someone explain why A

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Hello, kshitijtayal. This is a pretty difficult question if you are just starting out. However, if you focus on the basics and stick to meaning, you can arrive at the correct answer.


Note that the underlined portion is meant to explain the process of how geysers are formed. The independent clause at the head of the underline indicates that turbulence, a necessary ingredient in creating the geyser effect, leads to... eruptions. The logic is sound. The prepositional phrase that follows the comma outlines a subsequent event, an effect of the hydrothermal eruptions, and bursting in the underlined portion and destroying at the end of the sentence are parallel. In short, the arrow of causality is clear, and the sentence is free of grammatical errors.

[required] turbulence → hydrothermal eruptions → steam that bursts from a vent and destroys surrounding rock → the formation of a geyser


Where do I begin with this one? As odd as it may seem, the in front of hydrothermal eruptions is unwarranted. To refer to such a phenomenon in this restrictive sense, we would expect to have encountered these eruptions earlier on. Without such a reference, the article should be dropped altogether: the geyser [verb] hydrothermal eruptions. Then, affects is used in this sort of context to mean influences or has an effect on, not something such as causes. Thus, the eruptions are understood to have already been underway when the turbulence comes along. Of course, you should not have to be a volcanologist or geologist to work through a Sentence Correction question, so we might let that one slide. However, the next part, sometimes led by, adds nothing but confusion to this description. Are geysers formed only when this sometime or once-in-a-while development occurs? Furthermore, if you straighten out the passive construct led by, you get the notion that steam bursting from the vent sometimes leads to hydrothermal eruptions. It is unclear how escaping steam may cause these eruptions, rather than be an effect of them. Just as before, though, we should not have to be scientists to qualify an answer choice in SC, so we should look for other issues. And we happen to spot a grammatical problem with the stacked phrases at the end:

sometimes led by the steam bursting from the geyser's vent, often destroying the surrounding rock

Now, bursting and destroying are not parallel elements, and what, exactly, the destroying modifier is commenting on is unclear. To be honest, I would have so many doubts piled up by now that I would have already moved on.


Yes, the same confusing phrase stacking appears at the end of the underlined portion, only now we have three phrases: leading... with... often destroying. The chain of causality is unclear. However, the easier target, to my eye, appears in the use of the verb is earlier on. Notice that the appears just before the underlined portion and is therefore nonnegotiable, so this iteration leaves us with the following:

the turbulence is required to create the geyser effect

By turning required from a modifier into a subject complement (is required), the sentence has created the same problem we saw in the last answer choice with the: the turbulence, with no earlier reference to turbulence, should be, simply, turbulence.


Believe it or not, this is nothing more than a lengthy fragment—eruptions led by turbulence WHAT? There is no closure to the description of eruptions. Moreover, you should appreciate by now that the in the turbulence should not be there. Finally, the turbulence sometimes require is either a typo, in which require should be required, or an error in usage.


Again, we see a lengthy fragment. Everything from with on is part of an extended phrase, so we can ignore that portion. But if we lay bare the beginning of the answer choice, we get the following:

the eruptions led by the turbulence required to create the effect

You could not put a period at the end and call the above a sentence, since it is lacking a proper verb or object (to turn led by into a passive verb). You could take a more meaning-based approach to this option and seek to sort out the chain of events, but why bother when a clear grammatical error is present? Save those mental reserves for better challenges that may lie ahead.

Perhaps the question and answer choices make more sense now. Good luck with your studies.

- Andrew

Geysers are formed when subterranean igneous pressure forces underground water out into the open, and the turbulence required to create the geyser effect sometimes leads to hydrothermal eruptions, with steam bursting from the geyser’s vent and often destroying the surrounding rock.

a) turbulence required to create the geyser effect sometimes leads to hydrothermal eruptions, with steam bursting from the geyser’s vent and

b) turbulence required to create the geyser affects the hydrothermal eruptions, sometimes led by the steam bursting from the geyser’s vent,

c) turbulence is required to create the geyser effect, leading to hydrothermal eruptions, with steam bursting from the geyser’s vent,

d) hydrothermal eruptions led by the turbulence sometimes require to create the geyser effect, with steam bursting from the geyser’s vent and

e) hydrothermal eruptions sometimes led by the turbulence required to create the geyser effect, with steam bursting from the geyser’s vent and

It is important to understand the meaning conveyed inn order to the answer this question.
I have highlighted the points that can help you see why the meaning conveyed changes or doesn't make sense

HelloPrachiiPrasaad,

We hope this finds you well.

To answer your query, Option C is incorrect, as it alters the meaning of the sentence through the clause "turbulence is required to create the geyser effect, leading to hydrothermal eruptions"; the omission of the word "sometimes" incorrectly implies that the turbulence required to create the geyser effect always leads to hydrothermal eruptions; the intended meaning is that the turbulence, sometimes, leads to hydrothermal eruptions.

We hope this helps.
All the best!
Experts' Global Team

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