Complex sentence: Until 1990, this high and boarding school remained the only Lithuanian school outside areas controlled by the Soviet Union.It was attended by several well-known exiled Lithuanians such as the singer Lena Valaitis or the racing driver Kazim Vasiliauskas.
Split into simpler sentences: Until 1990, this high and boarding school remained the only Lithuanian school in the free world, attended by several known exiled Lithuanians. Among them the singer Lena Valaitis or the racing driver Kazim Vasiliauskas.