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