A few other points:

* se* can be used to convert an operator as if it were a selbri, so that its arguments are exchanged. For example:

li | ci | se | vu'u | vo | du | li | pa |

The-number | three | (inverse) | minus | four | equals | the-number | one. |

3 subtracted from 4 equals 1. |

The other converters of selma'o SE can also be used on operators with more than two operands, and they can be compounded to create (probably unintelligible) operators as needed.

Members of selma'o NAhE are also legal on an operator to produce a scalar negation of it. The implication is that some other operator would apply to make the bridi true:

The sense in which “plus” is the opposite of “minus” is not a mathematical but rather a linguistic one; negated operators are defined only loosely.

* la'e* and

li | re | su'i | re | du | li | na'ebo | mu |

The-number | 2 | plus | 2 | equals | the-number | non- | 5. |

2 + 2 = something other than 5. |

The digits 0-9 have rafsi, and therefore can be used in making lujvo. Additionally, all the rafsi have CVC form and can stand alone or together as names:

la | zel. | poi | gunta | la | tebes. | pu | nanmu |

Those-named | “Seven” | who | attack | that-named | “Thebes” | [past] | are-men. |

The Seven Against Thebes were men. |

Of course, there is no guarantee that the name
*zel.* is connected with the number rafsi: an alternative which cannot be misconstrued is:

la | zemei | poi | gunta |

Those-named-the | Sevensome | who | attack |

la | tebes. | pu | nanmu |

that-named | Thebes | [past] | are-men. |

Certain other members of PA also have assigned rafsi:
* so'a*,

A similar convention is used for the cmavo
* cu'o* of selma'o MOI, which is closely related to

The grammar of mekso as described so far imposes a rigid distinction between operators and operands. Some flavors of mathematics (lambda calculus, algebra of functions) blur this distinction, and Lojban must have a method of doing the same. An operator can be changed into an operand with
*ni'enu'a*, which transforms the operator into a matching selbri and then the selbri into an operand.

To change an operand into an operator, we use the cmavo
* ma'o*, already introduced as a means of changing a lerfu string such as

There is a potential semantic ambiguity in
*ma'o fy. [te'u]* if
* fy.* is already in use as a variable: it comes to mean
“the function whose value is always

`f`

”. However, mathematicians do not normally use the same lerfu words or strings as both functions and variables, so this case should not arise in practice.