As you may remember, Japanese is very particular in its way of counting. A special counter is used for different classes of objects or things. For non-Japanese, remembering which counter goes with which item can be baffling. Luckily, there is one factor that lends some sense to the madness: shape.
Bowls and Round Containers
Hai, which is sometimes pronounced pai, is a counter that applies to round containers. Cups and bowls then, are counted this way: ippai (“one bowlful”), ni hai (“two bowlfuls”), san bai, yon hai, go hai, roppai, nana hai, happai, kyu hai, juppai. The counters for “one,” “six,” “eight,” and “ten” are irregular in this category, so they are spelled, in roomaji, as single words. Otherwise, counters are separated from the class or category markers. Ultimately, any way of representing Japanese in roomaji is arbitrary. This way of representing the Japanese counting system has been chosen to make the counters more salient. Here is an example of a counter in action:
Itsumo, yuhan ni gohan wa san bai tabemasu yo.
I always eat three bowls of rice at dinner.
Concerns about your caffeine consumption can also be quelled with the response:
Asa wa koohii ni hai o nomimasu.
I drink two cups of coffee in the morning.
Balls and oranges are counted in the following way: ikko, ni ko, san ko, and so on. Note that only “one” is irregular. They are round, but they are not containers, which is why they are counted differently than cups and bowls.
Tall, Long, or Slender
Pencils, pens, dowels, towels, chopsticks, and long, slender roots can all be counted the same way: ippon, nihon, sanbon, yonhon, gohon, roppon,nanahon, happon, kyuhon, juppon. As long as it is tall and rounded or long and slender, this counter applies:
Enpitsu o roppon kaimashita.
I bought six pencils.
Bottles, too, can be counted in this way, but they also have a second, slightly more old-fashioned, counter, usually only used for one or two bot-tles: hitobin and futabin use the word for bottle (bin) so there is no question about what is being counted:
O-mizu o futabin kudasai.
Two bottles of water, please.
Though long and slender, snakes are not counted in the same category as pencils and towels. If you want to make people laugh, though, you might say, Hebi wa ippon imashita yo. (Snakes should be counted like other small animals: ippiki, nihiki, etc.)
Animals, Big and Small
Small animals such as raccoons, dogs, cats, squirrels, and fish have their own special counter. When you see a mama tanuki run across the road with her four babies, you can say:
Tanuki ga go hiki ita! There were five raccoons.
As with many other counting patterns, the terms for “one,” “six,” “eight,” and “ten” start with “p”; the terms for “two,” “four,” “five,” “seven,” and “nine” stick with “h” and for “three” it's “b”: ippiki, ni hiki, san biki, yon hiki, go hiki, roppiki, nana hiki, happiki, kyu hiki, juppiki.
Cows, elephants, pigs, and other large animals are counted with -too: ittoo, nitoo, santoo, and so on — the counters are regular. (This counter is actually a reference to the animals' massive heads.) When counting birds and rabbits, too, if you can remember ichi, ni, san, shi, etc. and the suffix -wa, you will be fine: Ichi wa, ni wa, san wa, and so on.
If you were hoping for one counter for all flat things, you will be disappointed. Beds and futons, pieces of paper, napkins, plates, envelopes, and sliced bread can all be counted with mai. However, books and bills must be counted with satsu:
Kami o roku mai kudasai.
Six pieces of paper, please.
Kono ni satsu o karitai-n desu.
I'd like to borrow these two books.
There used to be a time when killing rabbits was illegal in Japan. People still did it, though, because the rabbits were garden pests. If the police questioned you about what you had in your gunnysack (bunnysack), you could evade arrest by saying you had “go wa,” which meant you had five birds. This is why birds and rabbits still have the same counter, even though they do not have the same shape.