you use 万 for one 10,000, 三万 = 30,000 (3,0000), after 万 you repeat using 十/百/千
add commas every 4 digits vs 3 digits in english (2,1000 vs 21,000)
万, 千, 百(not白!!), 十 (10,000,1,000,100,10)
add one 零 when there is a zero in the middle of the number,not at the end,ex. 2005 = 两千零五,but 200 = 两百