se
This word is used in a unique way that helps facilitate the conversion of words between the different forms.
It's easy enough to say something "is a base noun\ le len "I am strong"
This only works if the word is already a base noun or base modifier. What if it's a base verb? How do you say something "is food" or "is edible" using the other derivations of makan? You can't say le makan, because that means "is eating". What do you do?
The solution is to use the modifier se meaning "real" or "existing". As a verb it is used to mean "to be" or "to exist". This allows you to use modifiers or wo/je phrases to use modifier or noun forms of any word you please.
In linguistics, this "to be" construction is called the $copula.
ne le se makan "This is edible", literally "This exists edibly"
ne le se je makan "This is food", literally "This exists in a manner\ le panli "That is divided", referring to the object that has been split
na le se je panli "That is a division", literally "that is dividedness" referring to the split in the object.
This allows you to use the noun or modifier form of any word when saying the phrase "is word\ se word\ se je word\ se je base modifier\ le cenpo, "this is large", than you'd say ne le se je cenpo, "this is largeness". In general this is most useful for using base verbs in their noun or modifier forms.
Implicit se
It does feel a bit clunky to be forced to use le se je to talk about noun forms all the time, so why not cut out a word? The particle je can never be a verb itself, but when it comes immediately after le it can be assumed that the verb is implicitly se. This shortens le se je to simply le je.
ne le se makan - "This is edible"
ne le je makan - "This is food"
ja le tope lan - "They are very good"
ja le je tope lan - "They are the embodiment of much goodness"
na le panli - "That is divided"
na le je panli - "That is a division"
This property of implicit se is also useful when using prepositions. Instead of saying na le se po tu, "that is for you", you could just say na le po tu and the verb se is simply implied.
matuwa mi le an $- $"My parent is at the store"
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