<p>The following is from a QAS.</p>
<p>Some plants use chemical signals that repel<a href="A">/u</a> insects and **also, these signals<a href="B">/b</a> help to put neighboring plants on alert so they can<a href="C">/u</a> mount their own defenses<a href="D">/u</a>.</p>
<p>The correct answer was B, "also, these"
Any help would be greatly appreciated. </p>
<p>Thanks.</p>
<p>I’m kind of interested too in the answer. I had the same problem with a question just like this one.</p>
<p>“Also” is unnecessary, and the comma immediately after it makes the structure as a whole ungrammatical. It is better and less wordy to say “Some plants use chemical signals that repel insects, and these signals help to put neighboring plants on alert. . . .”</p>
<p>Could you explain the strict grammatical reason for the error? Of course it doesn’t “sound” right but I trained myself to not trust my ear.</p>
<p>My guess is that since since the conjunction doesn’t follow after a comma, you can’t join the two insubordinate clauses. Instead, the second clause needs to be made into a subordinate clause by editing (B)</p>
<p>I don’t know, grammar school didn’t teach this to me, and High School assumed grammar school taught it.</p>