SC from previous posts : Navigators have known for thousands

[swara_ms]

Hi,

It so happened that i went through the following link.

Request any instructor to explain eliminating all the options.

gmat-t12452.html

In the explanation given by Ron, he mentioned usage of Present perfect. I get it, but i am confused with the following bit:

a reasonably clear picture has emerged of the patterns
and causes of ocean currents

is this construction correct??

"a reasonably clear picture of the patterns and causes of ocean currecnt has emerged."

I thought the verb "has emerged", would be better if modifiers or middlemen "of ocean currents" immediately follow the Noun/subject "picture".

Please help me clear off my thoughts, :) It is good to know how things work in GMAT world.

Warm Regards,
MS.

[macjas]

Hi there,

If you think about the logical construction of the sentence, it is the "clear picture" and NOT the "ocean currents" that has emerged. Grammatically too, this makes sense because prepositional phrases such as " of ocean currents" cannot be the subject that is being modified by the verb.

Another hint that you get that illustrates the relationship between "clear picture" emerging is the singular use of "has". Basically, patterns and causes of ocean currents has emerged would be wrong because "patterns and causes" would require a plural verb (have).

Does this make sense.

[swara_ms]

Thank you macwanjason. That helped. Would the following be right as well??

"a reasonably clear picture of the patterns and causes of ocean currents has emerged"

Warm Regards,
MS

[tim]

that looks fine to me. as for your request for an explanation of the wrong answers, was there something you needed clarified regarding the explanations provided in the post you linked to?