<p>1.The Empire State Building, the Sears Tower, the Canadian National Towereach (of these structures) (was) the (tallest) in the world at the time (they were) built.</p>
<p>What is the error. I put down "no error" but it's wrong. I know each is singular making "was" correct.</p>
<p>2.Most major air pollutants cannot be seen, although large amounts (of them) (concentrated in) cities (are visible) (as) smog.</p>
<p>Doesn't the error occur at C, since for comparison you need "as....as"?</p>
<p>3.The museum (is submitting) proposals (to several) foundations (in) the hope (to gain) funds to build a tropical butterfly conservatory. No error</p>
<p>I know the error is at D and the corrected form is "of gaining" but why?</p>
<ol>
<li>Intimacy, love, and marriage are three (different, if
interrelated, subjects).
(A) different, if interrelated, subjects
(B) interrelated subjects, being, however, different
(C) different subjects, whereas they are interrelated
(D) different subjects when interrelated
(E) subjects that are different although being
interrelated</li>
</ol>
<p>Why is the answer A and not D. I think D can also work here.</p>
<p>^ I was just looking over this thread, but I don’t understand silverturtle’s explanation for the error in the question with “of these structures.”</p>
<p>The subject of a sentence is never in an intervening prepositional phrase, which are exampled below in italics (simple subject and simple predicate are in bold):</p>
<p>“Oneof the horsesis tall.” </p>
<p>“Iseachof you ready?”</p>
<p>“Neitherof the guysis able to bring his llama to the party; it’s lame.” </p>
<p>The information in the intervening prepositional phrase has no grammatical effect on the rest of the sentence.</p>
<p>“eachof these structureswas the tallest in the world at the time it was built.” “each” is singular; there are no exceptions to this.</p>
<p>Oh, but the error is “they were,” right? When I skimmed over the page, I thought you were saying that the phrase “of these structures” was the error in the sentence.</p>