(1)计量单位符号和SI词头。(2)数学式中的运算符号、指数和对数函数符号、特殊常数符号、缩写符号等。例如:∑(连加),ln(自然对数),lg(常用对数),lim(极限),π(圆周率),max(最大值),min(最小值)等。(3)生物学中亚族以上(含亚族)的拉丁文学名及定名人。(4)化学元素符号。(5)仪器、元件、样品等的型号或代号。(6)用作序号和编号的字母。例如:附录A,组B。(7)外文的人名、地名、书名和机关名以及缩略语、首字母缩写词等。 (1) Unit of measure symbols and SI prefix. (2) Mathematical formula symbols, exponential and logarithmic function symbols, special constants symbols, abbreviations and so on. For example: Σ, ln (natural logarithm), lg (common logarithm), lim (limit), π (pi), max (maximum), min (minimum) and so on. (3) The Latin name and celebrity in Asians in biology (including Asians). (4) chemical element symbol. (5) Instruments, components, samples, etc. model or code. (6) Use as a serial number and a number of letters. For example: Appendix A, Group B. (7) names of foreign languages, place names, book titles and body names, abbreviations, acronyms and the like.