English verb conjugation
MUST WHISTLE

Regular verb: whistle - whistled - whistled

Affirmation

Simple form	V-ing form
I must whistle you must whistle she must whistle we must whistle you must whistle they must whistle	I must be whistling you must be whistling she must be whistling we must be whistling you must be whistling they must be whistling
Perfect	V-ing perfect
I must have whistled you must have whistled she must have whistled we must have whistled you must have whistled they must have whistled	I must have been whistling you must have been whistling she must have been whistling we must have been whistling you must have been whistling they must have been whistling

Negation

Simple form	V-ing form
I mustn't whistle you mustn't whistle she mustn't whistle we mustn't whistle you mustn't whistle they mustn't whistle	I mustn't be whistling you mustn't be whistling she mustn't be whistling we mustn't be whistling you mustn't be whistling they mustn't be whistling
Perfect	V-ing perfect
I mustn't have whistled you mustn't have whistled she mustn't have whistled we mustn't have whistled you mustn't have whistled they mustn't have whistled	I mustn't have been whistling you mustn't have been whistling she mustn't have been whistling we mustn't have been whistling you mustn't have been whistling they mustn't have been whistling

Interrogative form

Simple form	V-ing form
must I whistle? must you whistle? must she whistle? must we whistle? must you whistle? must they whistle?	must I be whistling? must you be whistling? must she be whistling? must we be whistling? must you be whistling? must they be whistling?
Perfect	V-ing perfect
must I have whistled? must you have whistled? must she have whistled? must we have whistled? must you have whistled? must they have whistled?	must I have been whistling? must you have been whistling? must she have been whistling? must we have been whistling? must you have been whistling? must they have been whistling?

Interro-negative form

Simple form	V-ing form
mustn't I whistle? mustn't you whistle? mustn't she whistle? mustn't we whistle? mustn't you whistle? mustn't they whistle?	mustn't I be whistling? mustn't you be whistling? mustn't she be whistling? mustn't we be whistling? mustn't you be whistling? mustn't they be whistling?
Perfect	V-ing perfect
mustn't I have whistled? mustn't you have whistled? mustn't she have whistled? mustn't we have whistled? mustn't you have whistled? mustn't they have whistled?	mustn't I have been whistling? mustn't you have been whistling? mustn't she have been whistling? mustn't we have been whistling? mustn't you have been whistling? mustn't they have been whistling?