3 writing questions!!

<p>Actually I asked 2 of the 3 in another post, but I didn't quite understand the explanation..</p>

<p>1.PSAT
Pictures of vipers drawn on the walls of caves suggest that prehistoric hunters may have used snake charms [for bringing] good luck.
I looked up in my Longman dictionary which has the phrase "use sth for doing sth". Yet the answer shows that "for bringing" is wrong. Why?! Is it that "use sth for doing sth" is not accepted in SAT/PSAT?</p>

<p>2.SAT
A thick growth of sunflowers [standing ten feet tall, their brown heads drooped] over the fence with the weight of their seeds.
The correct answer is "stood ten feet tall, their brown heads drooping"
Is it because "their brown heads" are part of the "sunflowers", thus the "sunflowers" should be the subject of the main cause?</p>

<p>3.The mistakes one makes growing up [is not necessarily repeated] by one's children.
I chose E, "are not necessary to be repeated", but the right answer is D, "are not necessarily repeated". Could anymore tell me why E is wrong?</p>

<ol>
<li><p>“standing ten feet tall, their brown heads drooped” are two separate sentences so they cannot be separated by comma. </p></li>
<li><p>My own explanation would be this: you should always choose the shortest version possible.</p></li>
</ol>

<p>1) to “suggest” corresponds to “to bring”, not “for bringing”. This is basically parallelism</p>

<p>You ask why:</p>

<p>The mistakes one makes growing up are not necessary to be repeated by one’s children.</p>

<p>is wrong.</p>

<p>“necessary” is an adjective. It modifies “mistakes”. The phrase “necessary mistakes” or “not necessary mistakes” doesn’t make much sense.</p>

<p>Thanks!!!
But I still can’t understand why “suggest” corresponds to “to bring”? Isn’t it “suggest that…”?</p>

<p>And why “A thick growth of sunflowers stood ten feet tall, their brown heads drooping over the fence with the weight of their seeds.” can be separated by a comma?</p>

<p>Well… In the first sentence, What follows “suggest that” is a noun clause in which “to bring” is directly corresponded to the word “use”. The structure in this clause is like “use sth to do sth”.</p>