I must besiege you must besiege he must besiege we must besiege you must besiege they must besiege
V-ing form
I must be besieging you must be besieging he must be besieging we must be besieging you must be besieging they must be besieging
Perfect
I must have besieged you must have besieged he must have besieged we must have besieged you must have besieged they must have besieged
V-ing perfect
I must have been besieging you must have been besieging he must have been besieging we must have been besieging you must have been besieging they must have been besieging
Negation
Simple form
I must not besiege you must not besiege he must not besiege we must not besiege you must not besiege they must not besiege
V-ing form
I must not be besieging you must not be besieging he must not be besieging we must not be besieging you must not be besieging they must not be besieging
Perfect
I must not have besieged you must not have besieged he must not have besieged we must not have besieged you must not have besieged they must not have besieged
V-ing perfect
I must not have been besieging you must not have been besieging he must not have been besieging we must not have been besieging you must not have been besieging they must not have been besieging
Interrogative form
Simple form
must I besiege? must you besiege? must he besiege? must we besiege? must you besiege? must they besiege?
V-ing form
must I be besieging? must you be besieging? must he be besieging? must we be besieging? must you be besieging? must they be besieging?
Perfect
must I have besieged? must you have besieged? must he have besieged? must we have besieged? must you have besieged? must they have besieged?
V-ing perfect
must I have been besieging? must you have been besieging? must he have been besieging? must we have been besieging? must you have been besieging? must they have been besieging?
Interro-negative form
Simple form
must I not besiege? must you not besiege? must he not besiege? must we not besiege? must you not besiege? must they not besiege?
V-ing form
must I not be besieging? must you not be besieging? must he not be besieging? must we not be besieging? must you not be besieging? must they not be besieging?
Perfect
must I not have besieged? must you not have besieged? must he not have besieged? must we not have besieged? must you not have besieged? must they not have besieged?
V-ing perfect
must I not have been besieging? must you not have been besieging? must he not have been besieging? must we not have been besieging? must you not have been besieging? must they not have been besieging?