details so that the operators can get the job done without unreasonable guesswork. Every detail should be accurate.Such completeness and precision are necessary because operators are to follow your instructions to the letter.Any missing or inaccurate information may lead to disastrous consequences. To achieve these results,you need to understand the task well,analyze your aud ience, choose a proper layout and use language skillfully. 重点讲解 1.围绕本课课文中的范例讲解产品使用说明文本的组成部分 Operating instructions may vary in their length and readership,but they typically consist of the following components: ◇ heading 0 introductory explanation ▣ tools or materials 0 warnings 0 general background ◇ sequenced instructions trouble-shooting guide These components are normally arranged in a sequence of sections,each with its own subheading,which identifies the purpose of the section.Of the sections,the heading, and sequenced instructions are essential while the other parts are optional. The heading is the title of the text.It gives information on what the text below is about.Wording of the heading must be clear and brief. The introductory explanation helps the operator by giving an overview of the operations.It may concern the purpose of the action,what it will achieve,and why this is a useful result.It may also tell him how much ground the instructions intend to cover. Tools or materials usually list any special tools or materials required for the operations.It obviously saves time if the operator can get them ready in advance. Warnings are necessary safety measures for operations.Some tasks involve certain hazards and operators need to be warned against them.General warnings are sometimes given at the end of instructions.We would recommend giving them at the start of the instructions,so that readers may remain alert from the beginning. Warnings concerning specific steps,say materials that are flammable or that give off noxious fumes,are given before he or she reaches the step for which the danger maydetails so that the operators can get the job done without unreasonable guesswork. Every detail should be accurate. Such completeness and precision are necessary because operators are to follow your instructions to the letter. Any missing or inaccurate information may lead to disastrous consequences. To achieve these results, you need to understand the task well, analyze your audience, choose a proper layout and use language skillfully. 重点讲解 1．围绕本课课文中的范例讲解产品使用说明文本的组成部分 Operating instructions may vary in their length and readership, but they typically consist of the following components:  heading  introductory explanation  tools or materials  warnings  general background  sequenced instructions  trouble-shooting guide These components are normally arranged in a sequence of sections, each with its own subheading, which identifies the purpose of the section. Of the sections, the heading, and sequenced instructions are essential while the other parts are optional. The heading is the title of the text. It gives information on what the text below is about. Wording of the heading must be clear and brief. The introductory explanation helps the operator by giving an overview of the operations. It may concern the purpose of the action, what it will achieve, and why this is a useful result. It may also tell him how much ground the instructions intend to cover. Tools or materials usually list any special tools or materials required for the operations. It obviously saves time if the operator can get them ready in advance. Warnings are necessary safety measures for operations. Some tasks involve certain hazards and operators need to be warned against them. General warnings are sometimes given at the end of instructions. We would recommend giving them at the start of the instructions, so that readers may remain alert from the beginning. Warnings concerning specific steps, say materials that are flammable or that give off noxious fumes, are given before he or she reaches the step for which the danger may