This form is designed to help students master the essential grammar, mechanics, punctuation, and usage rules needed for clear, thoughtful writing. All three versions of Sentence skills - Form A, Form B, and Sentence Skills with Readings , feature a flexible format and a wide variety of engaging examples, exercises and mastery tests. Each alternative version features different exercises, examples and mastery tests. Form B now includes a new opening section on the writing process, complete with a careful sequence of interesting activities that help students learn and master the principles of effecive writing, one step at a time.