Ключевые слова: background, bilingual, billboard, black, blackboard, board, bye, chalk, chalkboard, characters, chinese, class, concept, dirty, education, end, english, erased, farewell, goodbye, grunge, hand, handwriting, holding, knowledge, language, learn, learning, lesson, letters, meet, message, old, pattern, school, sign, smudged, solong, teaching, text, texture, translation, used, white, wood, word, write, writing,