Sentence Fragments Run-on Sentences Final -ed Final -s Subject-Verb Agreement Pronouns Spelling Consistency In the next eight chapters, you will concentrate on the way you use English. Most of the time, you use it effectively without thinking about it, but sometimes your usage may break the conventions of standard English. When that happens, even when your usage is appropriate and powerful within the environment where you are speaking or writing, in the larger environment of the English-speaking world, use of nonstandard English is considered an error. These chapters identify and explain some of the most common errors, using the structural terms of Part One. The chapters are organized to be independent of each other so that you can study only the ones that relate to your errors. Based on your writing, your teacher or tutor may assign chapters, or you can determine whether you need a chapter by taking the Pretest and letting the computer analyze your errors. The analysis will tell you what parts of the chapter you need to study. Then you can take the Mastery Test at the end to see whether you need to review sections and get more guidance from your teacher or tutor. The results of the Mastery Tests are e-mailed automatically to your instructor. Another way to select Part Two chapters for study is to keep track of the errors that show up in the writing that you've been doing during the course. If your teacher or tutor marks your papers using the Correction Key (Chart 15) in Part Four of the Study Guide, you can enter the number of errors in each category for each paper. After a few papers, you will see which chapters you need to study.