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