根据短文内容，从短文后的选项中选出能填入空白处的最佳选项，选项中有两项为多余选项。
Taking a math test can be pretty stressful. Even if you know the material, you can still get the problem wrong. Knowing how to go through your math test and check your work can save you from handing in a test full of mistakes that can be avoided. 【小题1】
Write it out
You can also check a math problem by writing everything out on paper. 【小题2】 Writing out math problems reduces your chances of missing anything to the lowest possible level, which is a mon cause of incorrect answers.
【小题3】
Make sure your answers work by doing the opposite procedure of what your problem calls for, including the answer you got the first time around. In other words, you would use the opposite of this addition problem—subtraction (减法)—to determine whether or not your answer is the correct one.
Plugging in
You may find that a variable(变量) isn’t good enough or have a problem where you have to solve for a variable. 【小题4】 This is the only real way to assure yourself that the answer you’ve found is correct.
Check for a reasonable answer
【小题5】 For example, if you get an answer in the millions and you know it should be in the thousands, you’ve likely misplaced a point. Go back through the work on your paper to make sure all of your formulas and calculations are correct. If everything looks okay, do the problem again and pare the result of the second try to what you’ve got on the first try.A．Do the oppositeB．Correct the answersC．Plug the variable in the equation (方程) to check it out.D．Therefore you’ll improve your grades, as well as your math skills.E. It also helps you to figure out everything after you have already finished the test.
F. If the result of a problem seems to make no sense, it indicates that the answer is incorrect.
G. This helps you to know what information you have and what information you need to solve.D
网友回答
(答案→)D
解析：本文为说明文。该文就如何解数学题及怎样验证答案进行了详述。
【小题1】D考查考生对上下文因果关系的理解能力及段落主旨的概括能力。根据上句“Knowing how to go through your math test and check your work can save you from handing in a test full of mistakes that can be avoided.”可知，此处应是知道了如何解题及验证答案有助于提高你的成绩和解题技巧。故选D
【小题2】G考查考生对上下文顺承关系的理解能力。根据上文“You can also check a math problem by writing everything out on paper.”及学生解数学题的常识性经验可知“把所有的已知条件都列出后，你就会知道该如何解题”。故选G。
【小题3】A考查考生对标题的提炼能力。根据该段内容和关键词 opposite 可知A项与其吻合。
【小题4】C考查考生对上下文顺承关系的理解能力。根据该段主题Plug in和该段中的variable一词可知C为正确选项。
【小题5】F考查考生对段落主题句的概括理解能力。该段主题“检查答案的合理性”，和F项中的“make sense”意思一致。