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