Original sentence: After the annexation of Lithuania into the Soviet Union in 1940, new eastern boundary of Lithuania (Lithuanian SSR) was delimited.In 1940, when Lithuania was incorporated into Soviet Union, a new boundary was drawn, which left most of Vilnius region in Belarusian SSR and Nazi Germany (later after World War II those areas became part of Poland).Some areas of the Vilnius region, however, were added to Lithuanian SSR (including towns of Švenčionys, Druskininkai and the village of Dieveniškės)
Edited sentence: After the annexation of Lithuania into the Soviet Union in 1940, a new eastern boundary of Lithuania (Lithuanian SSR) was delimited.In 1940, when Lithuania was incorporated into the Soviet Union, a new boundary was drawn, enlarging the de facto Lithuanian territory, though not to the full extent of the republic's claim.The control of the Vilnius region was partitioned between the Lithuanian SSR (including towns of Švenčionys, Druskininkai and the village of Dieveniškės), the Belarusian SSR and Nazi Germany (the latter territory was returned to Poland after World War II).The notable gain was the city of Vilnius, which became Lithuania's new capital