
Verbo irregular: grind - ground - ground
Forma simple | Forma con V-ing | 
| I could grind you could grind she could grind we could grind you could grind they could grind  | I could be grinding you could be grinding she could be grinding we could be grinding you could be grinding they could be grinding  | 
Perfecto | Perfecto con V-ing | 
| I could have ground you could have ground she could have ground we could have ground you could have ground they could have ground  | I could have been grinding you could have been grinding she could have been grinding we could have been grinding you could have been grinding they could have been grinding  | 
Forma simple | Forma con V-ing | 
| I couldn't grind you couldn't grind she couldn't grind we couldn't grind you couldn't grind they couldn't grind  | I couldn't be grinding you couldn't be grinding she couldn't be grinding we couldn't be grinding you couldn't be grinding they couldn't be grinding  | 
Perfecto | Perfecto con V-ing | 
| I couldn't have ground you couldn't have ground she couldn't have ground we couldn't have ground you couldn't have ground they couldn't have ground  | I couldn't have been grinding you couldn't have been grinding she couldn't have been grinding we couldn't have been grinding you couldn't have been grinding they couldn't have been grinding  | 
Forma simple | Forma con V-ing | 
| could I grind? could you grind? could she grind? could we grind? could you grind? could they grind?  | could I be grinding? could you be grinding? could she be grinding? could we be grinding? could you be grinding? could they be grinding?  | 
Perfecto | Perfecto con V-ing | 
| could I have ground? could you have ground? could she have ground? could we have ground? could you have ground? could they have ground?  | could I have been grinding? could you have been grinding? could she have been grinding? could we have been grinding? could you have been grinding? could they have been grinding?  | 
Forma simple | Forma con V-ing | 
| couldn't I grind? couldn't you grind? couldn't she grind? couldn't we grind? couldn't you grind? couldn't they grind?  | couldn't I be grinding? couldn't you be grinding? couldn't she be grinding? couldn't we be grinding? couldn't you be grinding? couldn't they be grinding?  | 
Perfecto | Perfecto con V-ing | 
| couldn't I have ground? couldn't you have ground? couldn't she have ground? couldn't we have ground? couldn't you have ground? couldn't they have ground?  | couldn't I have been grinding? couldn't you have been grinding? couldn't she have been grinding? couldn't we have been grinding? couldn't you have been grinding? couldn't they have been grinding?  |