hitotsu=one
ippon=one bottle
ippai=one glass
kudasai=please
"wo/を" = particle used to point at the object acted upon by the verb
Interestingly enough casually most people drop the "wo" and although KUDASAI is commonly translated as PLEASE, it originally comes from KUDASARU which means "give" or "send to/for" or "be grateful".
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Beer wo hitotsu.
Beer wo ippon.
Beer wo ippai.
Beer wo kudasai.
Beer wo hitotsu kudasai.
Beer wo ippon kudasai.
Beer wo ippai kudasai.
Namachu wo kudasai.
Namachu wo hitotsu kudasai.
Namachu wo ippon kudasai.
Namachu wo ippai kudasai.
beer for Japanese Order morons