<p>I dont know why the (__________) are right.</p>
<p>3.) Flints found in the region extending from the Nile Valley to the higlands of eastern Iraq (attests to) the presence of people there as long as one hundred years ago. </p>
<p>4.) By virtue of (its) size and supersensitive electronics, modern rasio telescopes are able to gather more waves and discriminate them with greater precision than earlier versions could.</p>
<p>6.) Air pollution caused by industrial fumes have been studied for years, but only recently (has) the harmful effects of noise pollution become known.</p>
<p>Basically, they are all referring to the wrong number. “Attests to” should be attest to, since it refers to “flints” which is plural.</p>
<p>“its” should be their, because it refers to “telescopes”, which is also plural.</p>
<p>And the same thing for the last example. “Has” should be have, because it refers to the harmful “effects”, not the harmful effect.</p>
<p>Hope that helps!</p>
<p>wow thanks that helped!</p>
<p>Golfer0210: Wait, for number 4, I thought “its” was wrong because it referred to “size and supersensitive electronics”? Can you explain why “its” is referring to telescopes?</p>
<p>If you read it carefully, and cut the first section, it looks like: “modern rasio telescopes are able to gather more waves and discriminate them with greater precision than earlier versions could.” The “electronics” are just another word that describes the telescopes, just like the size. </p>
<p>Does that make sense?</p>