You know, each unit of Polina Shinkina’s textbooks contains the Chinese characters decomposition table with the help of which I memorize and understand the Chinese characters!
Decomposition of the Chinese Character 四 sì ‘four’
四 sì four
囗 wéi enclosure
冂 jiōng down box
儿 ér boy
丿 piě slash
乚 yǐ second
一 yī one
囗冂 儿丿乚一
More about Chinese characters decomposition please check: The Chinese Character Decomposition Guidance by Polina Shinkina
http://www.lulu.com/content/e-book/the-chinese-character-decomposition-guidance/18847104 and
http://www.lulu.com/spotlight/polina985