The majority of intransitive verbs have only a transitive causative form: "pweipwei" > "kapweipwei", "to be stupid." Among verbs where "ka-" is productive, only adjectives and a few resultative intransitive verbs have both intransitive and transitive causative forms. Though the prefix is productive in many active and resultative verbs, it is not productive with neutral intransitive verbs, nor for a handful of intransitives denoting bodily functions such as "sneeze" ("asi"), "frown" ("lolok"), "be full" ("tip"), and "be smelly" ("ingirek"). The prefix "ka-" often has assimilative allophones depending on the stem, for example "soai" (to tell a tale) becomes "koasoia" (to talk), "dou" (to climb) becomes "kodoudou" (to trace one's ancestry), and "rir" (to be hidden) becomes "kerir" (secret sweetheart). As illustrated in these examples, the prefix often causes semantic differentiation, necessitating different constructions for literally causative meanings; "karirala", a different form employing "ka-", is used to mean "to make hidden."