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