Counting things

Japanese counts with a word chosen by the shape or kind of thing — 本(ほん) for long thin things, 枚(まい) for flat ones, 匹(ひき) for small animals — and the number usually follows the noun: 傘(かさ)が三本(さんぼん)あります, not "three umbrellas are". This list is about what happens when number and counter meet: sounds change, as in 一本(いっぽん), 三本(さんぼん), 六本(ろっぽん), and the days of the month from the 2nd to the 10th use old native numbers, 二日(ふつか), 三日(みっか). These have to be learned one by one; nobody works them out on the spot.