I must suffocate you must suffocate she must suffocate we must suffocate you must suffocate they must suffocate
V-ing form
I must be suffocating you must be suffocating she must be suffocating we must be suffocating you must be suffocating they must be suffocating
Perfect
I must have suffocated you must have suffocated she must have suffocated we must have suffocated you must have suffocated they must have suffocated
V-ing perfect
I must have been suffocating you must have been suffocating she must have been suffocating we must have been suffocating you must have been suffocating they must have been suffocating
Negation
Simple form
I mustn't suffocate you mustn't suffocate she mustn't suffocate we mustn't suffocate you mustn't suffocate they mustn't suffocate
V-ing form
I mustn't be suffocating you mustn't be suffocating she mustn't be suffocating we mustn't be suffocating you mustn't be suffocating they mustn't be suffocating
Perfect
I mustn't have suffocated you mustn't have suffocated she mustn't have suffocated we mustn't have suffocated you mustn't have suffocated they mustn't have suffocated
V-ing perfect
I mustn't have been suffocating you mustn't have been suffocating she mustn't have been suffocating we mustn't have been suffocating you mustn't have been suffocating they mustn't have been suffocating
Interrogative form
Simple form
must I suffocate? must you suffocate? must she suffocate? must we suffocate? must you suffocate? must they suffocate?
V-ing form
must I be suffocating? must you be suffocating? must she be suffocating? must we be suffocating? must you be suffocating? must they be suffocating?
Perfect
must I have suffocated? must you have suffocated? must she have suffocated? must we have suffocated? must you have suffocated? must they have suffocated?
V-ing perfect
must I have been suffocating? must you have been suffocating? must she have been suffocating? must we have been suffocating? must you have been suffocating? must they have been suffocating?
Interro-negative form
Simple form
mustn't I suffocate? mustn't you suffocate? mustn't she suffocate? mustn't we suffocate? mustn't you suffocate? mustn't they suffocate?
V-ing form
mustn't I be suffocating? mustn't you be suffocating? mustn't she be suffocating? mustn't we be suffocating? mustn't you be suffocating? mustn't they be suffocating?
Perfect
mustn't I have suffocated? mustn't you have suffocated? mustn't she have suffocated? mustn't we have suffocated? mustn't you have suffocated? mustn't they have suffocated?
V-ing perfect
mustn't I have been suffocating? mustn't you have been suffocating? mustn't she have been suffocating? mustn't we have been suffocating? mustn't you have been suffocating? mustn't they have been suffocating?