
Regular verb: author - authored - authored
Simple form | V-ing form | 
| I must author you must author she must author we must author you must author they must author  | I must be authoring you must be authoring she must be authoring we must be authoring you must be authoring they must be authoring  | 
Perfect | V-ing perfect | 
| I must have authored you must have authored she must have authored we must have authored you must have authored they must have authored  | I must have been authoring you must have been authoring she must have been authoring we must have been authoring you must have been authoring they must have been authoring  | 
Simple form | V-ing form | 
| I mustn't author you mustn't author she mustn't author we mustn't author you mustn't author they mustn't author  | I mustn't be authoring you mustn't be authoring she mustn't be authoring we mustn't be authoring you mustn't be authoring they mustn't be authoring  | 
Perfect | V-ing perfect | 
| I mustn't have authored you mustn't have authored she mustn't have authored we mustn't have authored you mustn't have authored they mustn't have authored  | I mustn't have been authoring you mustn't have been authoring she mustn't have been authoring we mustn't have been authoring you mustn't have been authoring they mustn't have been authoring  | 
Simple form | V-ing form | 
| must I author? must you author? must she author? must we author? must you author? must they author?  | must I be authoring? must you be authoring? must she be authoring? must we be authoring? must you be authoring? must they be authoring?  | 
Perfect | V-ing perfect | 
| must I have authored? must you have authored? must she have authored? must we have authored? must you have authored? must they have authored?  | must I have been authoring? must you have been authoring? must she have been authoring? must we have been authoring? must you have been authoring? must they have been authoring?  | 
Simple form | V-ing form | 
| mustn't I author? mustn't you author? mustn't she author? mustn't we author? mustn't you author? mustn't they author?  | mustn't I be authoring? mustn't you be authoring? mustn't she be authoring? mustn't we be authoring? mustn't you be authoring? mustn't they be authoring?  | 
Perfect | V-ing perfect | 
| mustn't I have authored? mustn't you have authored? mustn't she have authored? mustn't we have authored? mustn't you have authored? mustn't they have authored?  | mustn't I have been authoring? mustn't you have been authoring? mustn't she have been authoring? mustn't we have been authoring? mustn't you have been authoring? mustn't they have been authoring?  |