YOU SAID:
Hannah walks to the co-op to get some beer
INTO JAPANESE
ハンナはビールを飲みに生協に歩いて行く
BACK INTO ENGLISH
Hanna walks to co-op for a beer
INTO JAPANESE
ハンナはビールを買いに協力
BACK INTO ENGLISH
Hannah cooperates in buying beer
INTO JAPANESE
ハンナはビールの購入に協力しています
BACK INTO ENGLISH
Hannah is helping with the purchase of beer
INTO JAPANESE
ハンナはビールの購入を手伝っています
BACK INTO ENGLISH
Hanna is helping to buy beer
INTO JAPANESE
ハンナはビールを買うのを手伝っています
BACK INTO ENGLISH
Hanna is helping to buy beer
That didn't even make that much sense in English.