YOU SAID:
my potato has forty dads
INTO JAPANESE
私のじゃがいもは40人のお父さんがいます
BACK INTO ENGLISH
My potato has 40 fathers
INTO JAPANESE
私のじゃがいもには40人の父親がいます
BACK INTO ENGLISH
There are 40 fathers in my potato
INTO JAPANESE
私のじゃがいもには40人の父親がいます
BACK INTO ENGLISH
There are 40 fathers in my potato
That didn't even make that much sense in English.