Writing MC Help

<p>I took two writing tests, and these are the questions I am getting wrong: Parallel structure, Idioms, Verb tense and verb forms.</p>

<p>I keep getting these types of questions wrong, and I just don't know what to do to stop getting them wrong. If someone could please guide me to understanding how to solve these types of problems, I would really appreciate it. </p>

<p>I have Googled idioms and I'm just brought to web pages where people are arguing whether idioms are tested or not. I know that all of the idioms cannot be memorized, but guidance on this matter would really be helpful.</p>

<p>For parallel sentences, I have looked it up, but I don't exactly know what to do. </p>

<p>Thank you all in advance</p>