I may congratulate you may congratulate he may congratulate we may congratulate you may congratulate they may congratulate
V-ing form
I may be congratulating you may be congratulating he may be congratulating we may be congratulating you may be congratulating they may be congratulating
Perfect
I may have congratulated you may have congratulated he may have congratulated we may have congratulated you may have congratulated they may have congratulated
V-ing perfect
I may have been congratulating you may have been congratulating he may have been congratulating we may have been congratulating you may have been congratulating they may have been congratulating
Negation
Simple form
I mayn't congratulate you mayn't congratulate he mayn't congratulate we mayn't congratulate you mayn't congratulate they mayn't congratulate
V-ing form
I mayn't be congratulating you mayn't be congratulating he mayn't be congratulating we mayn't be congratulating you mayn't be congratulating they mayn't be congratulating
Perfect
I mayn't have congratulated you mayn't have congratulated he mayn't have congratulated we mayn't have congratulated you mayn't have congratulated they mayn't have congratulated
V-ing perfect
I mayn't have been congratulating you mayn't have been congratulating he mayn't have been congratulating we mayn't have been congratulating you mayn't have been congratulating they mayn't have been congratulating
Interrogative form
Simple form
may I congratulate? may you congratulate? may he congratulate? may we congratulate? may you congratulate? may they congratulate?
V-ing form
may I be congratulating? may you be congratulating? may he be congratulating? may we be congratulating? may you be congratulating? may they be congratulating?
Perfect
may I have congratulated? may you have congratulated? may he have congratulated? may we have congratulated? may you have congratulated? may they have congratulated?
V-ing perfect
may I have been congratulating? may you have been congratulating? may he have been congratulating? may we have been congratulating? may you have been congratulating? may they have been congratulating?
Interro-negative form
Simple form
mayn't I congratulate? mayn't you congratulate? mayn't he congratulate? mayn't we congratulate? mayn't you congratulate? mayn't they congratulate?
V-ing form
mayn't I be congratulating? mayn't you be congratulating? mayn't he be congratulating? mayn't we be congratulating? mayn't you be congratulating? mayn't they be congratulating?
Perfect
mayn't I have congratulated? mayn't you have congratulated? mayn't he have congratulated? mayn't we have congratulated? mayn't you have congratulated? mayn't they have congratulated?
V-ing perfect
mayn't I have been congratulating? mayn't you have been congratulating? mayn't he have been congratulating? mayn't we have been congratulating? mayn't you have been congratulating? mayn't they have been congratulating?