12.刪除:把多余的詞用斜線(\)劃掉.
增加:在缺詞處加一個漏字符號(∧),并在其下面寫出該加的詞.
修改:在錯的詞下劃-橫線,并在該詞下面寫出改正后的詞.
Thanks for your letter.I've thought a lot of about whether you should buy a laptop computer help you with your study.In my opinion,you'd better not.For one reason,it's very easy for you to develop some habit.Once you have it,such as playing computer games,see movies and so on,which will be a waste of time.For other reason,buying a laptop computer don't mean you can study well.If you want to make a progress,you need to put your heart into your study but work hard.Whether you had a computer or not is not the most important.Do you agree to me?Looking forward to your early reply!