Pinyin: Guo2 yu3 Definition: Chinese language (Mandarin), emphasizing its national nature/Chinese as a primary or secondary school subject/Chinese in the context of the Nationalist Government/Guoyu, book of historical narrative c. 10th-5th century BC
Pinyin: cheng2 yu3 Definition: Chinese set expression, often made up of 4 characters or two couplets of 4 characters each, often alluding to a story or historical quotation/idiom/proverb/saying/adage/set expression/CL:條|条[tiao2],本[ben3],句[ju4]
Pinyin: xie1 hou4 yu3 Definition: saying in which the second part, uttered after a pause or totally left out, is the intended meaning of the allegory presented in the first part
Decomposition Levels: Level 1: Only divided once. So only two components. Level 2: Radical Decomposition. The character gets decomposed into its lowest radical components. For the complete list visit the Radical wikipedia page. Level 3: Graphical Decomposition. Shows all the strokes & lowest level of components that make up the character. If you see questions marks or too many "block" characters, especially when it comes to level 3 decomposition you might need the correct font.