tons of grammar problems bother me.. help me!

<li>The historian wrote that the knights <using aluminum="" to="" lighten="" their="" armor="" predating=""> modern lightweight equipment.</using></li>
</ol>

<p>A) using aluminum to lighten their armor predating
B) using aluminum to lighten their armor and predate
C) using aluminum and lightening their armor, they predated
D) used aluminum to lighten their armor, and method predating
E) use of aluminum to lighten their armor predates</p>

<p>The answer is E but I just don’t get it. I think there should be apostrophe after the ‘knights’, like ‘the knights’ use of aluminum…blabla’ Shouldn’t it?
I’m really confused.</p>

<li>Like the emperors before him, Nero became another example of imperial decadence and corruption.</li>
</ol>

<p>A) Like the emperors before him, Nero
B) Like the precedent of the emperors before him
C) Nero, resembling the emperors before him,
D) In likeness to the emperors before him,
E) Nero’s conduct, like the emperors before him,</p>

<p>The answer is C. I picked A but I can’t really find any difference between those. </p>

<li>The economy had begun to slow its pace several years before the stock market crash, even though no one noticed it then.</li>
</ol>

<p>(I’ll just give you two choices, others are really absurd)</p>

<p>A) crash, even though no one noticed it then.
B) crash without anyone noticing.</p>

<p>The answer is B. But what is the difference anyway?</p>

<li>In spite of his critics’s accusations, the high school principal was <far away=""> from lenient.</far></li>
</ol>

<p><far away=""> should change into something. But I have no idea. </far></p>

<li>Original: The Opium War against the British in 1848 was a huge defeat for the Chinese.
Right answer: In the Opium War of 1848, the Chinese suffered a huge defeat at the hands of the British.</li>
</ol>

<p>I thought the answer was too wordy and I picked ‘As it is now’.</p>

<li>Original: He presented some of Britain’s greatest wares. To this display, however, the Chinese Emperor Qianlong replied that neither he nor his empire needed any British goods.</li>
</ol>

<p>Right answer: In reaction to the display of Britain’s greatest wares, the Chinese Emperor Qianlong replied that neither he nor his empire needed any British goods.</p>

<p>I know the original should be changed, but the answer doesn’t seem right.</p>

<p>I really do need your help( I’m taking Oct. test…)
Thanks a lot for reading my thread!</p>

<p>somebody help me plz?...</p>