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