I must balk you must balk he must balk we must balk you must balk they must balk
V-ing form
I must be balking you must be balking he must be balking we must be balking you must be balking they must be balking
Perfect
I must have balked you must have balked he must have balked we must have balked you must have balked they must have balked
V-ing perfect
I must have been balking you must have been balking he must have been balking we must have been balking you must have been balking they must have been balking
Negation
Simple form
I must not balk you must not balk he must not balk we must not balk you must not balk they must not balk
V-ing form
I must not be balking you must not be balking he must not be balking we must not be balking you must not be balking they must not be balking
Perfect
I must not have balked you must not have balked he must not have balked we must not have balked you must not have balked they must not have balked
V-ing perfect
I must not have been balking you must not have been balking he must not have been balking we must not have been balking you must not have been balking they must not have been balking
Interrogative form
Simple form
must I balk? must you balk? must he balk? must we balk? must you balk? must they balk?
V-ing form
must I be balking? must you be balking? must he be balking? must we be balking? must you be balking? must they be balking?
Perfect
must I have balked? must you have balked? must he have balked? must we have balked? must you have balked? must they have balked?
V-ing perfect
must I have been balking? must you have been balking? must he have been balking? must we have been balking? must you have been balking? must they have been balking?
Interro-negative form
Simple form
must I not balk? must you not balk? must he not balk? must we not balk? must you not balk? must they not balk?
V-ing form
must I not be balking? must you not be balking? must he not be balking? must we not be balking? must you not be balking? must they not be balking?
Perfect
must I not have balked? must you not have balked? must he not have balked? must we not have balked? must you not have balked? must they not have balked?
V-ing perfect
must I not have been balking? must you not have been balking? must he not have been balking? must we not have been balking? must you not have been balking? must they not have been balking?