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