I must counteract you must counteract he must counteract we must counteract you must counteract they must counteract
V-ing form
I must be counteracting you must be counteracting he must be counteracting we must be counteracting you must be counteracting they must be counteracting
Perfect
I must have counteracted you must have counteracted he must have counteracted we must have counteracted you must have counteracted they must have counteracted
V-ing perfect
I must have been counteracting you must have been counteracting he must have been counteracting we must have been counteracting you must have been counteracting they must have been counteracting
Negation
Simple form
I mustn't counteract you mustn't counteract he mustn't counteract we mustn't counteract you mustn't counteract they mustn't counteract
V-ing form
I mustn't be counteracting you mustn't be counteracting he mustn't be counteracting we mustn't be counteracting you mustn't be counteracting they mustn't be counteracting
Perfect
I mustn't have counteracted you mustn't have counteracted he mustn't have counteracted we mustn't have counteracted you mustn't have counteracted they mustn't have counteracted
V-ing perfect
I mustn't have been counteracting you mustn't have been counteracting he mustn't have been counteracting we mustn't have been counteracting you mustn't have been counteracting they mustn't have been counteracting
Interrogative form
Simple form
must I counteract? must you counteract? must he counteract? must we counteract? must you counteract? must they counteract?
V-ing form
must I be counteracting? must you be counteracting? must he be counteracting? must we be counteracting? must you be counteracting? must they be counteracting?
Perfect
must I have counteracted? must you have counteracted? must he have counteracted? must we have counteracted? must you have counteracted? must they have counteracted?
V-ing perfect
must I have been counteracting? must you have been counteracting? must he have been counteracting? must we have been counteracting? must you have been counteracting? must they have been counteracting?
Interro-negative form
Simple form
mustn't I counteract? mustn't you counteract? mustn't he counteract? mustn't we counteract? mustn't you counteract? mustn't they counteract?
V-ing form
mustn't I be counteracting? mustn't you be counteracting? mustn't he be counteracting? mustn't we be counteracting? mustn't you be counteracting? mustn't they be counteracting?
Perfect
mustn't I have counteracted? mustn't you have counteracted? mustn't he have counteracted? mustn't we have counteracted? mustn't you have counteracted? mustn't they have counteracted?
V-ing perfect
mustn't I have been counteracting? mustn't you have been counteracting? mustn't he have been counteracting? mustn't we have been counteracting? mustn't you have been counteracting? mustn't they have been counteracting?