There are two types of counters in Japanese language. One of them,hitotsu, futatsu, mittsu type is a Japanese original counter and the other, ichi, ni, san type is Chinese one. Japanese type can be used independently used from
1to 10 only but Chinese type can be used number and counter together like
Japanese type---Three hamburgers, please. Haｎbaagaa o mittsu kudasai.
Chinese type --- Three hamburgers, please. Hambaagaa o san-ko kudasai.
Please tell me how many cups of coffe you drink or other items.
mayoneezu o kaimasu.
buta ga imasuka.
no-to o kaimasu.
Each object has a specific counter, -hon for long objects like pencils and bottles ,-dai for big machine like cars and computers so on. Japanese type replace Chinese type especially small objects. You can use hitotsu, futats, when you don't know the specific counter for the specific object.
-mai for paper, dishes. -kai for floors -satsu for books, magazines. -hon for penciles, bottles. -hun for minutes -ban for nights -nichi for days -nin for people
4 yon/shi/ yo
7 nana/ shichi
9 kyuu/ ku