Sentence Correction

I did not notice "to sharply rise" SPLIT infinitive.... though I marked A , as it sounded good...

I thought 'should' means moral obligation, but I dont understand how does this meaning fit the requirement of the sentence?

Can somebody pls clarify?

ashish2104 wrote:I thought 'should' means moral obligation, but I dont understand how does this meaning fit the requirement of the sentence?

Can somebody pls clarify?

Note : here usage of should as subjunctive form.
[when 'should' is used as moral obligation then generally it is wrong in GMAT ]

Here : Should === if

both are largely the same. there are minor rhetorical differences, but nothing that will make or break a question on the test.

"if" is a subordinating conjunction, and isn't part of a verb construction. therefore, it's used with normal verbs.
"should" is a helping verb. therefore, it's used with infinitive type verbs (i.e., the infinitive form, minus the "to").

examples:
if you are late tomorrow, you'll be fired.
should you be late tomorrow, you'll be fired.

Should present metal prices continue their sharp rise, the value of the copper in a penny will soon be greater than the face value of the coin.

a. Should present metal prices continue their sharp rise, ("should" can be used as "if", correct asnwer)
b. If present metal prices are continuing their sharp rise, ("are continuing" is wrong)
c. If present metal prices continue to sharply rise, ("to sharply rise" is wrong)
d. Continuation of sharply rising metal prices should mean that (wordy)
e. Metal prices' sharp rise continuing should mean that (wordy)

Should present metal prices continue their sharp rise, the value of the copper in a penny will soon be greater than the face value of the coin.

a. Should present metal prices continue their sharp rise,
b. If present metal prices are continuing their sharp rise,
c. If present metal prices continue to sharply rise,
d. Continuation of sharply rising metal prices should mean that
e. Metal prices' sharp rise continuing should mean that


really i dont understand why the answer is A and i chose C and i was wrong....
i read the forum because it once discussed in the forums. Manhattan forum said " using "their" here is wrong but still chose A, the other forum said the correct structure is if X then Y. However i recall i was taught " if +S+V, S+V", there is no " then" between two clauses. i dont understand so please reexamplain