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