Verbs have valency, which is how many “arguments” they have. For example intransitive means no arguments (or only one, the subject), transitive, means one (or two, subject and object). So a typical lojban verb (gismu) works like this:
x1 leaves from x2 via route x3.
This compares to toki pona which has 7 slots marked by either e or a preposition.
lon tomo mi
tawa pilin pona
tan wile moku mi
poka jan pona mi
I eat an (object), with a (tool), like (similar object), at (a location), for (some goal, benefit), from (some place or causal reason), with (a collaborator). That is it. There are no more slots. This compares to English where we have many more slots via a much larger list of prepositions.
The toki pona verb always follows the same pattern, the lojban one has different meanings for different slots depending on the verb (gismu)
Of course the toki pona phrase can be re-arranged, except for the e phrases, which must come first. Also, routinely, the prepositional phrases can be modifiers for a single content word, which doesn’t have an analogy in lobjan, AFAIK (which isn’t much).
Also, another observation. If there are only 6 slots, marked by a particle on the head verb, wouldn’t these turn into case markers, like in a single generation of human use?