he grind?" "did he grind?" "has he ground?" "had he ground?"
"does she grind?" "did she grind?" "has she ground?" "had she ground?"
"does it grind?" "did it grind?" "has it ground?" "had it ground?"
"do we grind?" "did we grind?" "have we ground?" "had we ground?"
"do they grind?" "did they grind?" "have they ground?" "had they ground?" 