
Regular verb: check - checked - checked
Simple form | V-ing form | 
| I may check you may check she may check we may check you may check they may check  | I may be checking you may be checking she may be checking we may be checking you may be checking they may be checking  | 
Perfect | V-ing perfect | 
| I may have checked you may have checked she may have checked we may have checked you may have checked they may have checked  | I may have been checking you may have been checking she may have been checking we may have been checking you may have been checking they may have been checking  | 
Simple form | V-ing form | 
| I mayn't check you mayn't check she mayn't check we mayn't check you mayn't check they mayn't check  | I mayn't be checking you mayn't be checking she mayn't be checking we mayn't be checking you mayn't be checking they mayn't be checking  | 
Perfect | V-ing perfect | 
| I mayn't have checked you mayn't have checked she mayn't have checked we mayn't have checked you mayn't have checked they mayn't have checked  | I mayn't have been checking you mayn't have been checking she mayn't have been checking we mayn't have been checking you mayn't have been checking they mayn't have been checking  | 
Simple form | V-ing form | 
| may I check? may you check? may she check? may we check? may you check? may they check?  | may I be checking? may you be checking? may she be checking? may we be checking? may you be checking? may they be checking?  | 
Perfect | V-ing perfect | 
| may I have checked? may you have checked? may she have checked? may we have checked? may you have checked? may they have checked?  | may I have been checking? may you have been checking? may she have been checking? may we have been checking? may you have been checking? may they have been checking?  | 
Simple form | V-ing form | 
| mayn't I check? mayn't you check? mayn't she check? mayn't we check? mayn't you check? mayn't they check?  | mayn't I be checking? mayn't you be checking? mayn't she be checking? mayn't we be checking? mayn't you be checking? mayn't they be checking?  | 
Perfect | V-ing perfect | 
| mayn't I have checked? mayn't you have checked? mayn't she have checked? mayn't we have checked? mayn't you have checked? mayn't they have checked?  | mayn't I have been checking? mayn't you have been checking? mayn't she have been checking? mayn't we have been checking? mayn't you have been checking? mayn't they have been checking?  |