"REGARD AS" and "CONSIDER TO BE"

Many historians regard the time of the Heian court as the greatest period in Japanese history.
A. Same
B. regard the time of the Heian court to be
C. regard the time of the Heian court to have been
D. consider that the time of the Heian court is
E. consider the time of the Heian court as

The correct relevant idiomatic expression are "regard as" and "consider to be". Eliminate B, C and E. D is wrong tense. A is correct.

sentence with-
consider as   X
regard to be  X

conclusion that VS conclusion of

Henry never showed effort, and his essays were always pedestrian; since his latest paper is nearly flawless, the obvious conclusion seems to be one of a more advanced student researching and writing at least part of Henry's impressive essay.
A. Same
B. conclusion of a more advanced student researching and writing at least part of Henry's impressive essay seems obvious
C. conclusion seems obvious that at least part of Henry's impressive essay was researched and written by a more advanced student.
D. conclusion of at least part of Henry's impressive essay having been researched and written by a more advanced student seems obvious.
E. seemingly obvious conclusion is that a more advanced student would have researched and written at least part of Henry's impressive essay.

"Conclusion that" is correct.
"Conclusion of" is wrong. Therefore, A, B and D are out.
The tense is wrong in E. C is correct.

SO MUCH......AS

SO MUCH.......AS  is a very frequent idiom in the GMAT.

so much by X as by Y
so much because of X as because of Y

Q. Some analysts of the latest technological advances argue that technology moves forward not so much because of great sparks of ideas but because of smaller contributions, such as improved practices, better laboratories and more knowledgeable designers.
A. same
B. because of great sparks of ideas as the results of
C. because of great sparks of ideas as because of
D. through great sparks of ideas but through
E. through great sparks of ideas but results from

answer is C

Q. Ripe peaches are marked not so much by their color but instead by their firmness and fullness of aroma.
A. Same
B. rather than
C than
D. as
E. so much as

Correct Answer: D

JUST AS...SO TOO

JUST AS...SO TOO is idiomatically correct.

E.g. Just as the Russian communists of the early 20th century believed that they were overcoming the tyranny of the czars, so too did the Chinese communists believe they were avoiding the misrule of the Guomindang.

"LESS THAN" VS "LESSER THAN"

Q. With total sales of less than three hundred thousand dollars and fewer new subscribers than last year, the New England Theater Company is in danger of losing its building.

A. of less than three hundred thousand dollars and fewer

B. lower than three hundred thousand dollars and less

C. lesser than three hundred thousand dollars and fewer

D. fewer than three hundred thousand dollars and less

E. of fewer than three hundred thousand dollars and of fewer

For countable nouns we use "fewer".  So, it comes down to A, C and E. E uses "of fewer", which is not correct. "Lesser than" is idiomatically incorrect, "Less Than" is correct. Therefore, A is correct.

"FORBID FROM" "FORBID THAT"

"FORBID FROM" "FORBID THAT" both are idiomatically incorrect.

e.g.
No school policies forbid a teacher to scold a student. (correct)

FEWER THAN

FEWER THAN is correct idiom just as LESS THAN, GREATER THAN etc.

If the draft is not re-instated, less people will join the army in the coming 10 years than did in any other 10-year period in our nation's history.
A. Same
B. less people will be joining the army in the coming 10 years as
C. Fewer people will join the army in the coming 10 years as
D. Fewer people will be joining the army in the coming 10 years as
E. Fewer people will join the army in the coming 10 years than

"Fewer...as" is not the correct idiom when there is comparison, as is used for showing similarity so only option E is correct.

NO LESS AN X THAN Y

Yes, there is an idiom in English- no less an x than y.

For e.g. no less a superstar than Rajni Kant.

Q. No less an expert than John H. McWhorter has claimed that African-American children do poorly in schools because of implicit social pressure to fail academically.

A. Same.
B. Not less an expert
C. Not less an expert
D. Not less an expert than
E. An expert not less than

Correct choice is A as per the idiom.

Like vs. As

Like is used to compare nouns.

As is used to compare actions.

In Turkey, coffee is traditionally drunk very strong, much as the french do.
A) much as the French do
B) much like the French do
C) much as it is by the French
D) much as it is in France
E) much like it is in France

OA is D

The comparison is between two countries Turkey and France, so the choice is now D or E.
The focus of the sentence is on the action (of drinking), so it should be "as" and not "like".

Another exampleà
Try this instead: Susan, like her mother, is a good singer.

Or:
Joe, like Mary, has a cat.
Joe has a cat, as does Mary.

Both of the above are correct - I just have to write the sentence differently.
I can't say: Joe has a cat, like Mary. I have to put Mary over near Joe if I want to use "like."

Compare with vs. Compare to

Rule 1: Compare to compares unlike things, whereas compare with compares like things.

Rule 2: Compare to is used to stress the resemblance. Compare with can be used to show either similarity or difference but is usually used to stress the difference.

"X is Y" vs "X is like Y" vs "X is similar to Y"

See this question:

Q. Trying to mimic some of the pitch variations of a dolphin chattering is the same as attempting to sing like a sick parakeet when one is intoxicated; the complete lack of harmony and apparent randomness of the noise means the human vocal chords are completely incapable of reproducing these sounds.

A. the same as attempting to sing like a sick parakeet when one is intoxicated.
B. similar to an intoxicated person singing like a sick parakeet
C. like singing like a sick parakeet as an intoxicated person
D. the same as an intoxicated person singing like a sick parakeet
E. like the intoxicated person is singing like a sick parakeet

It involves parallel structure. You have to look carefully to figure out what form the comparison takes. The comparison is not one of similarity, it is on of equality. Saying "x is y" is quite different from saying "x is like y" or "x is similar to y". Choices B, C and E all change the fundamental underlying concept of the sentence. Choise D disrupts the parallel structure. The parallel structure is "trying to mimic" and "attempting to sing". A is the correct answer.

INTERVAL BETWEEN

Whenever within a sentence you see the world INTERVAL make yourself very clear that it's talking about two parts so it has to be followed by "BETWEEN".

For e.g.

Because the economic cycle in the USA changes little during its twenty year interval between recessing , it is fairly easy for analyst to predict analogous trends in the stock market.
a) between recessing
b) of recessing
c) between its recessions
d) of it recessions
e) as it recesses

Since, its talking about the USA's economic cylce the pronoun should be "its", therefore answer is C.

OF A TYPE vs IS A TYPE

Have a look at this sentence-


Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they
believe is a type previously unknown to science.
(A) that they believe is
(B) that they believe it to be
(C) they believe that it is of
(D) they believe that is
(E) they believe to be of

The correct answer is E.
The correct usage here is ..they believe to be of a type previously unknown to science.

DISTINGUISH BETWEEN.....AND.....

We normally have the confusion between the following two sentences-

DISTINGUISH BETWEEN X AND Y

DISTINGUISH BETWEEN X FROM Y

Well the correct idiomatic expression is-
DISTINGUISH BETWEEN X AND Y

ESTIMATED AT vs ESTIMATED TO BE

As per the GMAT the correct usage by thumb rule is "ESTIMATED TO BE"

See this example:
"The fossils of x are estimated to be y years old...."


But there is another twist to it-
"estimated at" should be used only when the author is trying to indicate a location at which the estimation was made.


So, the conclusion is-


The rock that the Z-team found yesterday was estimated at the silicon valley by A-team earlier.


The rock that the Z-team found is estimated to be 5000 years old.

RATE AT vs RATE OF

“The Rate of” Vs “The Rate at”

Consider the following example:

The rate at which people drive cars.(Correct)
The rate of cars driven by people. -- This option changes the meaning and is wrong here.

Whenever we refer to the speed/velocity we use it as THE RATE AT.

Whenever we refer to the prices we use it as THE RATE FOR.

For e.g.

State officials report that soaring rates of liability insurance have risen to force cutbacks in the operations of everything from local governments and school districts to day-care centers and recreational facilities.

(A) rates of liability insurance have risen to force

(B) rates of liability insurance are a force for

(C) rates for liability insurance are forcing

(D) rises in liability insurance rates are forcing

(E) liability insurance rates have risen to force

The correct answer is C as it refers to the price of liability insurance.

DIFFERENT FROM

While doing the comparison we use "Different From".

Please make a note that "Different From" is the correct usage instead of "Different than".

A Consequence Of

"A Consequence Of"

The ozone hole is largely a consequence of the use of the carbon pollutants

.

"WHETHER OR NOT" & "NUMBERS OF"

Let me put some light on the wrong idiomatic expressions that we most commonly face in the GMAT.

Out of the many wrong idiomatic expressions the most frequent ones are:

"Whether or not"

"Numbers of"

Both of the above are always incorrect in the GMAT.

NOT ONLY....BUT ALSO

NOT ONLY....BUT ALSO is probably the most commonly used idiom in the GMAT.

Consider this sentence please-

NOT ONLY is ROY tired BUT he is hungry.

Now, the above sentence is a wrong idiomatic expression.

The correct usage is:

NOT ONLY is ROY tired BUT he is ALSO hungry.

NOTE: Its not always essential to place BUT and ALSO together, they can be in a split as shown in the above sentence.

"NATIVE OF" VS "NATIVE FROM"

Here is a sentence for you:

A large percentage of New York City residents are native from other countries.

I'm sure when you hear this sentence you must be suspecting incorrect idiomatic expression, right?
Yes, in the sentence: "native from" sounds a little unusual.

So, what should be the correct usage??

Ok, here it is-

A large percentage of New York City residents are NATIVES OF other countries.

This sentence is the correct usage.

"RANGE FROM X TO Y" VS "RANGE BETWEEN"

Idioms are expressions that have unique forms. There is no hard and fast rule for determining the form of an idiom.

RANGE FROM X TO Y is an idiomatic expression.
RANGE BETWEEN is incorrect.