I must deskill you must deskill he must deskill we must deskill you must deskill they must deskill
V-ing form
I must be deskilling you must be deskilling he must be deskilling we must be deskilling you must be deskilling they must be deskilling
Perfect
I must have deskilled you must have deskilled he must have deskilled we must have deskilled you must have deskilled they must have deskilled
V-ing perfect
I must have been deskilling you must have been deskilling he must have been deskilling we must have been deskilling you must have been deskilling they must have been deskilling
Negation
Simple form
I must not deskill you must not deskill he must not deskill we must not deskill you must not deskill they must not deskill
V-ing form
I must not be deskilling you must not be deskilling he must not be deskilling we must not be deskilling you must not be deskilling they must not be deskilling
Perfect
I must not have deskilled you must not have deskilled he must not have deskilled we must not have deskilled you must not have deskilled they must not have deskilled
V-ing perfect
I must not have been deskilling you must not have been deskilling he must not have been deskilling we must not have been deskilling you must not have been deskilling they must not have been deskilling
Interrogative form
Simple form
must I deskill? must you deskill? must he deskill? must we deskill? must you deskill? must they deskill?
V-ing form
must I be deskilling? must you be deskilling? must he be deskilling? must we be deskilling? must you be deskilling? must they be deskilling?
Perfect
must I have deskilled? must you have deskilled? must he have deskilled? must we have deskilled? must you have deskilled? must they have deskilled?
V-ing perfect
must I have been deskilling? must you have been deskilling? must he have been deskilling? must we have been deskilling? must you have been deskilling? must they have been deskilling?
Interro-negative form
Simple form
must I not deskill? must you not deskill? must he not deskill? must we not deskill? must you not deskill? must they not deskill?
V-ing form
must I not be deskilling? must you not be deskilling? must he not be deskilling? must we not be deskilling? must you not be deskilling? must they not be deskilling?
Perfect
must I not have deskilled? must you not have deskilled? must he not have deskilled? must we not have deskilled? must you not have deskilled? must they not have deskilled?
V-ing perfect
must I not have been deskilling? must you not have been deskilling? must he not have been deskilling? must we not have been deskilling? must you not have been deskilling? must they not have been deskilling?