at the Ministry of Education, Solomonick created a broad selection of teaching aids geared to different types of learning communities. Among his works were grammars for Russian and English speakers, phonetic exercises for them and for Ethiopian Jews, and lessons for presentation in radio broadcasts to the former Soviet Union. The pinnacle of his activities during this period was his creation of a manual for Ulpan teachers, "The Principal Concepts in Teaching Additional Languages to Adults", and his compilation of "Comparative Grammars" between Hebrew, on the one hand, and grammatical phenomena in English, French, Spanish, Russian, Georgian, Amharic, and Persian, on the other hand. In his final years at the Ministry of Education, Solomonick began to familiarize the Ulpan teachers with computers, laying the groundwork for the introduction of computer-aided learning as one of the mainstays of the Ulpans' activities. After his retirement, Solomonick began writing grammars and dictionaries for English and Russian speakers at the Mila Publication Co. Between 1995 and 2003, he wrote, edited, or initiated a score of different dictionaries and grammars. These works were collected into two teaching kits: one for English-speakers and the other for Russian-speakers. The kits are on sale to this day, and can also be purchased on the Internet. In addition to his linguistic activities, Solomonick is deeply involved in the field of semiotics. He has written a number of books and articles on the topic and spoken at international conferences. He is currently recognized as an expert in the field. Not only has he developed his own concept of general semiotics, he has also tried to apply it to various branches of semiotics, including linguistics, pedagogy, advertising, and cartography. Solomonick views general semiotics as the “trunk” of the “tree” of semiotics; every semiotic branch sprouts from this trunk, and all are united by the common laws and principles represented by the trunk. His fascination with the philosophy of cognition resulted in some books on the topic published in Petersburg (in Russian) and also at Cambridge University (in English). Meanwhile, one of his books – ″Essay on General Semiotics″ – was translated and published in China. Semiotic theory Solomonick's theory of general semiotics is founded on the classification of sign-systems by their basic signs (taxons). The theory identifies five types of sign-systems: natural, iconic, linguistic, notational, and mathematical; each type includes systems with the same types of basic signs (see illustration). In