Germany's main Jewish organization on Thursday introduced a new book to help recent Jewish immigrants from the former Soviet Union learn German language skills and Jewish culture. Germany's Jewish community is the fastest growing in the world, with recently immigrated Jews from Russia and other former Soviet countries accounting for more than half of the roughly 105,000 Jews now living here. While the immigrants have strengthened their numbers, German Jews have at times been critical that newcomers' lack both German language skills and knowledge of Jewish culture. This makes it more difficult for them to assimilate. The new book, put together by the Central Council of Jews, seeks to address both of those problems, with specifically tailored lesson in the German language and Jewish culture.