I must gainsay you must gainsay she must gainsay we must gainsay you must gainsay they must gainsay
V-ing form
I must be gainsaying you must be gainsaying she must be gainsaying we must be gainsaying you must be gainsaying they must be gainsaying
Perfect
I must have gainsaid you must have gainsaid she must have gainsaid we must have gainsaid you must have gainsaid they must have gainsaid
V-ing perfect
I must have been gainsaying you must have been gainsaying she must have been gainsaying we must have been gainsaying you must have been gainsaying they must have been gainsaying
Negation
Simple form
I mustn't gainsay you mustn't gainsay she mustn't gainsay we mustn't gainsay you mustn't gainsay they mustn't gainsay
V-ing form
I mustn't be gainsaying you mustn't be gainsaying she mustn't be gainsaying we mustn't be gainsaying you mustn't be gainsaying they mustn't be gainsaying
Perfect
I mustn't have gainsaid you mustn't have gainsaid she mustn't have gainsaid we mustn't have gainsaid you mustn't have gainsaid they mustn't have gainsaid
V-ing perfect
I mustn't have been gainsaying you mustn't have been gainsaying she mustn't have been gainsaying we mustn't have been gainsaying you mustn't have been gainsaying they mustn't have been gainsaying
Interrogative form
Simple form
must I gainsay? must you gainsay? must she gainsay? must we gainsay? must you gainsay? must they gainsay?
V-ing form
must I be gainsaying? must you be gainsaying? must she be gainsaying? must we be gainsaying? must you be gainsaying? must they be gainsaying?
Perfect
must I have gainsaid? must you have gainsaid? must she have gainsaid? must we have gainsaid? must you have gainsaid? must they have gainsaid?
V-ing perfect
must I have been gainsaying? must you have been gainsaying? must she have been gainsaying? must we have been gainsaying? must you have been gainsaying? must they have been gainsaying?
Interro-negative form
Simple form
mustn't I gainsay? mustn't you gainsay? mustn't she gainsay? mustn't we gainsay? mustn't you gainsay? mustn't they gainsay?
V-ing form
mustn't I be gainsaying? mustn't you be gainsaying? mustn't she be gainsaying? mustn't we be gainsaying? mustn't you be gainsaying? mustn't they be gainsaying?
Perfect
mustn't I have gainsaid? mustn't you have gainsaid? mustn't she have gainsaid? mustn't we have gainsaid? mustn't you have gainsaid? mustn't they have gainsaid?
V-ing perfect
mustn't I have been gainsaying? mustn't you have been gainsaying? mustn't she have been gainsaying? mustn't we have been gainsaying? mustn't you have been gainsaying? mustn't they have been gainsaying?