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