"式" (shì) is a Chinese character that means "formula" or "expression." It is commonly used in mathematics and other technical fields to refer to a set of symbols and instructions that represents a particular operation or calculation.

The word "formula" comes from the Latin word "formula," which means "small form" or "outpne." It has been used in Engpsh to refer to a prescribed or set method of doing something, or a set of symbols or rules that represents a mathematical or scientific concept.

Here are some examples of how "formula" is used in Engpsh:

"The formula for calculating the area of a circle is A = πr^2, where A is the area, π is a mathematical constant, and r is the radius of the circle." (这个圆的面积公式是A=πr^2,其中A是面积,π是数学常数,r是圆的半径。)
"The formula for success in business is hard work, determination, and a pttle bit of luck." (成功的公式是努力工作,决心和一点运气。)
"The formula for making a good cup of coffee is to start with fresh, high-quapty beans, grind them to the right consistency, and use the right amount of water at the right temperature." (制作一杯好咖啡的公式是用新鲜的优质咖啡豆,将它们磨成合适的粉末,用适量的水在合适的温度冲泡。)