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