On grammatical class:

ca'a
modal aspect: actuality/ongoing event.
ka'e
modal aspect: innate capability; possibly unrealized.
nu'o
modal aspect: can but has not; unrealized potential.
pu'i
modal aspect: can and has; demonstrated potential.
bi'ai
Sumtcita indicating that the bridi must be true under the conditions indicated by the tagged sumti.
ka'enai
modal aspect: impossible to be realized
na'epu'i
modal aspect: has never, and perhaps cannot; other-than-demonstrated-ability.

In definition:

cmavrca'a
x1 is the selma'o "CAhA".

In notes:

saptoda
x1 is a part of Lojban text representing rule 'simple-tense-modal' according to the first edition of the book 'The Complete Lojban Language'.