Help with a few writing MC please

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1

<p>Parentheses indicate where the sentence is underlined</p>

<ol>
<li>A radio system consists of a means of transforming sounds into electromagnetic (waves and of transmitting those waves through space; after this those waves must be transformed) back into sounds.</li>
</ol>

<p>A: waves and of transmitting those waves through space; after this those waves must be transformed
B: waves, transmitting the waves through space, and transforming them
C: waves, of transmitting them through space, and then the translation of them
D: waves and of transmitting them through space; after this the waves have to be translated
E: waves, of the transmitting of those waves through space and of translating same</p>

<p>B is the answer, but I felt that B changed the meaning of the sentence because it implies that the radio system is able to change the waves back into sounds...not sure if that makes sense or if I'm thinking too much into it. Help?</p>

<ol>
<li>I have gone (to) (only one) football game (after) I (graduated) from high school. (No error). </li>
</ol>

<p>The answer is (after) , which I just plain don't understand.</p>

<p>Help is much appreciated.</p>

2

<ol>
<li><p>You’re thinking too much into it. B avoids the errors in parallelism and ambiguous pronouns that the other choices make.</p></li>
<li><p>“after” should be “since” (this is because the sentence contains the present perfect tense).</p></li>
</ol>

3

<p>Makes sense, thanks for your help.</p>