
Verbo regular: knock - knocked - knocked
Forma simple | Forma com V-ing | 
| I may knock you may knock he may knock we may knock you may knock they may knock  | I may be knocking you may be knocking he may be knocking we may be knocking you may be knocking they may be knocking  | 
Perfeito | Perfeito com V-ing | 
| I may have knocked you may have knocked he may have knocked we may have knocked you may have knocked they may have knocked  | I may have been knocking you may have been knocking he may have been knocking we may have been knocking you may have been knocking they may have been knocking  | 
Forma simple | Forma com V-ing | 
| I mayn't knock you mayn't knock he mayn't knock we mayn't knock you mayn't knock they mayn't knock  | I mayn't be knocking you mayn't be knocking he mayn't be knocking we mayn't be knocking you mayn't be knocking they mayn't be knocking  | 
Perfeito | Perfeito com V-ing | 
| I mayn't have knocked you mayn't have knocked he mayn't have knocked we mayn't have knocked you mayn't have knocked they mayn't have knocked  | I mayn't have been knocking you mayn't have been knocking he mayn't have been knocking we mayn't have been knocking you mayn't have been knocking they mayn't have been knocking  | 
Forma simple | Forma com V-ing | 
| may I knock? may you knock? may he knock? may we knock? may you knock? may they knock?  | may I be knocking? may you be knocking? may he be knocking? may we be knocking? may you be knocking? may they be knocking?  | 
Perfeito | Perfeito com V-ing | 
| may I have knocked? may you have knocked? may he have knocked? may we have knocked? may you have knocked? may they have knocked?  | may I have been knocking? may you have been knocking? may he have been knocking? may we have been knocking? may you have been knocking? may they have been knocking?  | 
Forma simple | Forma com V-ing | 
| mayn't I knock? mayn't you knock? mayn't he knock? mayn't we knock? mayn't you knock? mayn't they knock?  | mayn't I be knocking? mayn't you be knocking? mayn't he be knocking? mayn't we be knocking? mayn't you be knocking? mayn't they be knocking?  | 
Perfeito | Perfeito com V-ing | 
| mayn't I have knocked? mayn't you have knocked? mayn't he have knocked? mayn't we have knocked? mayn't you have knocked? mayn't they have knocked?  | mayn't I have been knocking? mayn't you have been knocking? mayn't he have been knocking? mayn't we have been knocking? mayn't you have been knocking? mayn't they have been knocking?  |