The imperfective category, marked by the suffix -arε or, more frequently, by the reduced form –a, includes progressive, habitual and iterative uses. Most stative verbs are unacceptable with imperfective inflection (e.g. poko ‘like, be fond of’ and glofu ‘believe’), but habu ‘have’ occasionally takes it, and suku ‘want’ appears more frequently with imperfective than without; the presence or absence of imperfective marking appears not to change the interpretation of the state described by these verbs. In contrast, where imperfective is used with a verb derived from an adjective, a process interpretation results rather than a state interpretation.
Source: Kouwenberg 2007: 29
Source: Kouwenberg 2007: 29
Source: Kouwenberg 1996: 33