Like is used to compare only nouns. (i.e. use like to say two things are similar, and let the clause that follows tell how they are similar)
The earth, like other planets, spins on an axis.
Like other planets, the earth spins on an axis.

As is used to compare clauses. (i.e. use as if two actions are similar)
A globe spins around an axis, as does the Earth itself.

A few rules of thumb:
(1) you should have two verbs in a sentence with an As comparison, one verb in a sentence with a Like comparison.
(2) Like comparisons work the same way as noun modifiers--make sure the right nouns are touching!
(3) The GMAT tends to use like mostly at the beginning of sentences. It is tough to put like at the end of a sentence and get the meaning right.

During an ice age, the buildup of ice at the poles and the drop in water levels near the equator speed up the Earth’s rotation, like a spinning figure skater whose speed increases when her arms are drawn in.

(A) like a spinning figure skater ...LIKE compares nouns, but the comparison is Earth's rotation = a spinning figure skater. Should be Earth = skater.

(B) like the increased speed of a figure skater...LIKE compares nouns, but the comparison is Earth's rotation = the increased speed. Should be Earth = skater.

(C) like a figure skater...LIKE compares nouns, but the comparison is Earth's rotation = a figure skater. Should be Earth = skater.

(D) just as a spinning figure skater (modifier: who increases speed by drawing in her arms)...AS incorrectly compares nouns. There is no verb in the as phrase, as required.

(E) just as a spinning figure skater increases speed by drawing in her arms. CORRECT. AS correctly compares the verbs speed up and increases speed.
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from other forum
"You are comparing actions, so you must use "just as."
Between D and E, D is not logically parallel. Remember, you are comparing the actions. You are comparing the increase in earth's rotation to the increase in speed of the skater. D uses "who" to modify the skater, and as a result, the increase in rotation is incorrectly compared to the skater, instead of the increase in speed."
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anyways....she is ' the man'....

Hey All,

I didn't check the other thread, but I thought I'd add a few more details in here. As some have said, it is a comparison issue, but the notion of comparing "actions" versus "things" is a dangerous one. I warn you that the explanations below are complicated, so feel free to ask follow-up questions. First, let's consider a simple comparison example:

Like running, swimming is great.

No one would argue that we aren't comparing actions in that sentence, but these are gerunds (verbal nouns), so we have to use "like". Thus the distinction between "actions" and "nouns" starts to break down. Now watch this:

Like Einstein, Dave was a really smart guy.

You could argue here that we're comparing people (Einstein and Dave) OR actions (they were both smart guys), yet we still need "like".

In reality, we only use AS when comparing CLAUSES (a phrase with a verb in a tense). "Like Einstein" has no verb in a tense, so we use LIKE. Similarly, "Like running" doesn't have a verb in a tense, so we use LIKE. Let's consider the answer choices in this light...

257. During an ice age, the buildup of ice at the poles and the drop in water levels near the equator speed up the Earth’s rotation, like a spinning figure skater whose speed increases when her arms are drawn in.

(A) like a spinning figure skater whose speed increases when her arms are drawn in
PROBLEM: Believe it or not, in this iteration of the sentence, LIKE is more correct. Think of it like this. I could correctly write, "Faster and faster turned the merry-go-round, like a spinning figure skater." In this sentence, the second phrase has NO VERB in a tense, so LIKE is okay (we're comparing the NOUN "merry-go-round" with the NOUN "spinning figure skater" (spinning is an adjective there)).

Now before you all get up in arms, obviously this answer choice is in correct. We WANT to compare actions (namely the way that the Earth's rotation speeds up, as well as the skater's rotation). But in this answer choice, if we just threw in AS, we wouldn't have the verb that we need to make this a clause. The verb "increases" is inside a modifying phrase, initiated by the relative pronoun "whose", so we lack an actual action to be comparing. Complicated, I know, but a critical piece of information you must understand to answer these brutal comparison/modifier questions. (I'd also add that the wording of this particular sentence makes it sound like we're comparing "rotation" to "spinning figure skater", which makes it even more wrong.)

(B) like the increased speed of a figure skater when her arms are drawn in
PROBLEM: Comparison logic. It's not the increased speed we want to compare to, though the LIKE is correct (this isn't a clause, as the verb "are drawn in" is within another modifying phrase, initiated by the relative pronoun "when").

(C) like a figure skater who increases speed while spinning with her arms drawn in
PROBLEM: Comparison logic. It's not like a figure skater who increases speed with her arms drawn in, but it's like THE WAY speed increases when the arms are drawn in (as nitya said, we need the clause, not the noun).

(D) just as a spinning figure skater who increases speed by drawing in her arms
PROBLEM: Fragmentary. Just like we saw in A, the "who" phrase is a modifier, so we never get a main verb here, meaning we CANNOT use AS correctly here. It would need to be something like "just as a spinning figure skater who draws in her arms increases her speed". Now we have the verb "increases" as a main verb, so we're allowed to use "as".

(E) just as a spinning figure skater increases speed by drawing in her arms
ANSWER: Voila. We get the AS, and the main verb "INCREASES".

As I said above, I'm happy to answer follow-up questions here. Hope this helped!

-t
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This problem tests the use of comparison markers Like Vs As. In this SC problem the non-underlined portion has a clause, thus the answer choice requires the conjunction (comparison marker) "AS". "Like" is used to compare two nouns or noun phrases.

The expected use of AS in this SC problem is "X does/did something, just as Y does/did something"
e.g. Mary aced her LSAT exam, just as John cracked his GMAT test.

Here is the difference between D & E
(D) just as a spinning figure skater who increases speed by drawing in her arms
This choice only contains the noun phrase with "spinning figure skater" with modifier "who increases speed by drawing in her arms". Hence, the noun "spinning figure" is being compared with non-underlined clause "the buildup of ice at the poles and the drop in water levels near the equator speed up the Earth’s rotation". Hence its the improper use of comparison marker.
(E) just as a spinning figure skater increases speed by drawing in her arms
Correct. This choice correctly compares two clauses
- the buildup of ice at the poles and the drop in water levels near the equator speed up the Earth’s rotation
- just as a spinning figure skater increases speed by drawing in her arms
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Hi,

As and Like can be used for comparison. But like cannot be used when we are stating a function.

For Comparison: Like has to be followed by Noun, and as has to be followed by clause.

For Function: As has to be followed by a noun. We dont have anything for Like since we cannot use Like to states someone or somethings function.

For more detail understanding of Like and As. Please see the below articles.

1. As vs Like

2. Usage of like

Hope it helps.
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(A) like a spinning figure skater whose speed increases when her arms are drawn in
like is used to compare nouns only, but here it is compared to an action.

(B) like the increased speed of a figure skater when her arms are drawn in
same error as in A.

(C) like a figure skater who increases speed while spinning with her arms drawn in
same error as in A and B.

(D) just as a spinning figure skater who increases speed by drawing in her arms
as + noun is used to describe the role/function

(E) just as a spinning figure skater increases speed by drawing in her arms
correct

Point 1: Nicola Tesla was a scientist, not an example of radio

Point 2: Whenever we use a semicolon, the following clause should be an independent clause with an action verb.

(A) radio, such as Nikola Tesla ----- This choice makes Nikola as an example of radio.

(B) radio; including as Nikola Tesla --- we are using a semi-colon here and what follows is not a clause, because there is no verb for Nikola

(C) radio, including Nikola Tesla --- Now this choice uses a comma and a semi-colon. So, the following phrase starting with including, a modifier, is appropriate. Correct choice.

(D) radio; not least among them being Nikola Tesla -- No verb for Nikola in the latter part. A fragment

(E) radio; especially Nikola Tesla – No verb for Nikola in the second part.
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Comparison is between why earth's rotation speed increases (buildup of ice at the poles and the drop in water levels near the equator causes this) and how skater's speed increases (drawing in the arms by skater causes this).

(A) like a spinning figure skater whose speed increases when her arms are drawn in Comparison is not between spinning figure skater and rotating earth
(B) like the increased speed of a figure skater when her arms are drawn in comparison is not between increased speed of skater and earth
(C) like a figure skater who increases speed while spinning with her arms drawn in comparison is not between figure skater and rotating earth
(D) just as a spinning figure skater who increases speed by drawing in her arms Just as is followed by noun
(E) just as a spinning figure skater increases speed by drawing in her arms correct choice, we are comparing that how earth increases speed and how skater does that

E is the correct choice
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Let me try to make it simple:

During an ice age, the build-up of ice at the poles and the drop in water levels near the equator speed up the Earth’s rotation, like a spinning figure skater whose speed increases when her arms are drawn in.
(A) like a spinning figure skater whose speed increases when her arms are drawn in
(B) like the increased speed of a figure skater when her arms are drawn in
(C) like a figure skater who increases speed while spinning with her arms drawn in
(D) just as a spinning figure skater who increases speed by drawing in her arms
(E) just as a spinning figure skater increases speed by drawing in her arms

Learning 1. Like is used to compare (show similarity) between nouns and AS is used to compare (show similarity) between two CLAUSES.
Learning 2: Like as other modifiers follow the touch rule i.e. it should be just prior to what is modifies
Learning 3: When we use AS to show similarity between two clauses, we should always have a main verb with “AS” clause.

Now here, we are comparing the “ Drop in water level speed up the earth rotation” clause. SO we must have a clause. And when there is a cause, we need AS not LIKE. So, ABC are out.
In D, we don’t have any main verb after AS. “who increases speed by drawing in her arms” is a modifier. Hence, we are lacking a clause. – D is out – Not Parallel as well.
In E, “just as a spinning figure skater increases speed” is a clause wth main verb “Increases” and it is rightly comparing to the first clause “ Drop in water level speed up the earth rotation”.

E is the answer.