formulae

名词 formula:

1. a group of symbols that make a mathematical statement
   同义词：formula, expression
2. directions for making something
   同义词：recipe, formula
3. a conventionalized statement expressing some fundamental principle
   同义词：formula
4. a representation of a substance using symbols for its constituent elements
   同义词：formula, chemical formula
5. something regarded as a normative example
   同义词：convention, normal, pattern, rule, formula
6. a liquid food for infants
   同义词：formula
7. (mathematics) a standard procedure for solving a class of mathematical problems
   同义词：rule, formula

1. `How d'you do' and `Excuse me' are social formulae.
   ｀你好＇和｀对不起＇是社交中的客套语。