Shulchan Arukh, Orach Chayim 185/שולחן ערוך·אורח חיים קפ״ה

1Birkas Hamazon can be recited in any language

2One needs to hear what he is reciting but if he does not hear he has fulfilled his obligation as long as he articulated the words

3There is an opinion that that when a ba’al habayis is with his children and wife he must recite birkas hamazon out loud so they can discharge their obligation with his recitation

4Even if one got significantly drunk to the point that the person is unable to properly speak, one is still able to bless the Birkat HaMazon.

5If one blessed the Birkat HaMazon and [found] that there was feces near him or that he had been drunk, Tosafos and Rabbi Asher ben Yehiel were unsure if one needed to go back and re-bless the Birkat HaMazon, but not for urine; for that, one need not re-bless Birkat HaMazon.