This paper discusses how perfectivity is manifested in the Baltic language Latvian and Livonian, the Finnic language of the Uralic languages, spoken in Latvia, by means of verbal prefixes. It offers a comparison of the Latvian and Livonian systems. Due to the majority status of Latvian, and resulting bilingualism among Livonian speakers, the Latvian influence on Livonian has been remarkable on lexical and grammatical levels. The use of Latvian verbal prefixes in Livonian is a demonstrative example of this. This research belongs to the field of contact linguistics and compares aspect systems synchronically.

My research hypothesis is that the two systems are similar to some extent because of the shared basis, but the Livonian system has also developed separately. The research is based on empirical data derived from the corpora (www.korpuss.lv) for Latvian, and for Livonian, from unpublished recordings and published written material (Mägiste 2006).

In Latvian, there are 11 verbal prefixes, which are used as perfectivity markers. The use of the verbal prefixes in Livonian generally corresponds with the Latvian use. However, in Latvian verbal prefixes are the primary way to express perfectivity, whereas in Livonian other ways exist. In both languages the prefix usually simultaneously expresses perfectivity and alters the lexical meaning of the verb spatially, temporally, or quantitatively. (LVG §1187, §1188.)

Unlike in Latvian, only a part of verbal prefixes are used as perfective markers in Livonian. This applies to the most frequent prefixes, while infrequent prefixes usually alter the lexical meaning of verbs. The most frequent prefix in Livonian, however, seems to be developing a new use divergent from Latvian: It acts as a perfective marker also in cases lacking a counterpart in Latvian. This prefix might be considered as a default perfectivizing prefix in Livonian, whereas in Latvian the prefix does not have this function.