On grammatical class:

sei
start discursive (metalinguistic) bridi.
ti'o
mathematical expression (mex) operator precedence (discursive).
cei'e
define following selbri with sentence or tu'e...tu'u clause
le'au
Start property which sets the meaning of {le} in the surrounding text.

In definition:

cmavrsei
x1 is the selma'o "SEI".

In notes:

skubancu
x1 is metalinguistic with respect to the expression by x2 of text x3 for audience x4 via medium x5 .
lu'ei
convert a grammatical quotation to a tanru unit; x1 expresses/says the quoted text for audience x2 via expressive medium x3.
slurume
x1 is a part of Lojban text representing rule 'free' according to the first edition of the book 'The Complete Lojban Language'.
upsi
x1 (entity) acknowledges making mistake x2 (property of x1)