Predicates can be modified to indicate the time at which something occurred (English tense) with the optional structure words "na" (present), "pa" (past) and "fa" (future). Thus "Le matma na vedma" means "The mother is (now) selling", while "Le matma fa vedma" means "The mother will sell". Marking the verb for tense is optional, so the word "ga" can be used when the time is not being specified.