The majority of students cant use abbreviations and symbols for note taking, and therefore it often results in omitting some important contents.

大多数学生在作英语笔记记录时，不会使用缩写词和符号，从而遗漏一些重要内容就在所难免。

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In order to ensure that the public is on the same page and has the same understanding of abbreviations and symbols, a summary will be provided on the background essential to the course.

为了确保学员进度相同，并对缩写和符号有相同的理解，本部分将给出摘要，介绍课程中必不可少的背景知识。

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Convenient alphabetic abbreviations, called mnemonics, and other symbols represent operation codes, storage locations, and data elements.

便捷的字母缩写，所谓的记忆法，以及其他符号所代表的运作守则，存放位置，及数据元素。

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As many have said, the language trend that first started with email and later text messaging has been to use more abbreviations, and even symbols (emoticons or smiley faces) to convey ideas, emotions or context.

FORBES: The Changing Grammar of Communicating Ideas