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