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