I must air-cool you must air-cool she must air-cool we must air-cool you must air-cool they must air-cool
V-ing form
I must be air-cooling you must be air-cooling she must be air-cooling we must be air-cooling you must be air-cooling they must be air-cooling
Perfect
I must have air-cooled you must have air-cooled she must have air-cooled we must have air-cooled you must have air-cooled they must have air-cooled
V-ing perfect
I must have been air-cooling you must have been air-cooling she must have been air-cooling we must have been air-cooling you must have been air-cooling they must have been air-cooling
Negation
Simple form
I mustn't air-cool you mustn't air-cool she mustn't air-cool we mustn't air-cool you mustn't air-cool they mustn't air-cool
V-ing form
I mustn't be air-cooling you mustn't be air-cooling she mustn't be air-cooling we mustn't be air-cooling you mustn't be air-cooling they mustn't be air-cooling
Perfect
I mustn't have air-cooled you mustn't have air-cooled she mustn't have air-cooled we mustn't have air-cooled you mustn't have air-cooled they mustn't have air-cooled
V-ing perfect
I mustn't have been air-cooling you mustn't have been air-cooling she mustn't have been air-cooling we mustn't have been air-cooling you mustn't have been air-cooling they mustn't have been air-cooling
Interrogative form
Simple form
must I air-cool? must you air-cool? must she air-cool? must we air-cool? must you air-cool? must they air-cool?
V-ing form
must I be air-cooling? must you be air-cooling? must she be air-cooling? must we be air-cooling? must you be air-cooling? must they be air-cooling?
Perfect
must I have air-cooled? must you have air-cooled? must she have air-cooled? must we have air-cooled? must you have air-cooled? must they have air-cooled?
V-ing perfect
must I have been air-cooling? must you have been air-cooling? must she have been air-cooling? must we have been air-cooling? must you have been air-cooling? must they have been air-cooling?
Interro-negative form
Simple form
mustn't I air-cool? mustn't you air-cool? mustn't she air-cool? mustn't we air-cool? mustn't you air-cool? mustn't they air-cool?
V-ing form
mustn't I be air-cooling? mustn't you be air-cooling? mustn't she be air-cooling? mustn't we be air-cooling? mustn't you be air-cooling? mustn't they be air-cooling?
Perfect
mustn't I have air-cooled? mustn't you have air-cooled? mustn't she have air-cooled? mustn't we have air-cooled? mustn't you have air-cooled? mustn't they have air-cooled?
V-ing perfect
mustn't I have been air-cooling? mustn't you have been air-cooling? mustn't she have been air-cooling? mustn't we have been air-cooling? mustn't you have been air-cooling? mustn't they have been air-cooling?