I must shiver you must shiver he must shiver we must shiver you must shiver they must shiver
V-ing form
I must be shivering you must be shivering he must be shivering we must be shivering you must be shivering they must be shivering
Perfect
I must have shivered you must have shivered he must have shivered we must have shivered you must have shivered they must have shivered
V-ing perfect
I must have been shivering you must have been shivering he must have been shivering we must have been shivering you must have been shivering they must have been shivering
Negation
Simple form
I must not shiver you must not shiver he must not shiver we must not shiver you must not shiver they must not shiver
V-ing form
I must not be shivering you must not be shivering he must not be shivering we must not be shivering you must not be shivering they must not be shivering
Perfect
I must not have shivered you must not have shivered he must not have shivered we must not have shivered you must not have shivered they must not have shivered
V-ing perfect
I must not have been shivering you must not have been shivering he must not have been shivering we must not have been shivering you must not have been shivering they must not have been shivering
Interrogative form
Simple form
must I shiver? must you shiver? must he shiver? must we shiver? must you shiver? must they shiver?
V-ing form
must I be shivering? must you be shivering? must he be shivering? must we be shivering? must you be shivering? must they be shivering?
Perfect
must I have shivered? must you have shivered? must he have shivered? must we have shivered? must you have shivered? must they have shivered?
V-ing perfect
must I have been shivering? must you have been shivering? must he have been shivering? must we have been shivering? must you have been shivering? must they have been shivering?
Interro-negative form
Simple form
must I not shiver? must you not shiver? must he not shiver? must we not shiver? must you not shiver? must they not shiver?
V-ing form
must I not be shivering? must you not be shivering? must he not be shivering? must we not be shivering? must you not be shivering? must they not be shivering?
Perfect
must I not have shivered? must you not have shivered? must he not have shivered? must we not have shivered? must you not have shivered? must they not have shivered?
V-ing perfect
must I not have been shivering? must you not have been shivering? must he not have been shivering? must we not have been shivering? must you not have been shivering? must they not have been shivering?