English verb conjugation
MUST LUMBER

Regular verb: lumber - lumbered - lumbered

Affirmation

Simple form	V-ing form
I must lumber you must lumber she must lumber we must lumber you must lumber they must lumber	I must be lumbering you must be lumbering she must be lumbering we must be lumbering you must be lumbering they must be lumbering
Perfect	V-ing perfect
I must have lumbered you must have lumbered she must have lumbered we must have lumbered you must have lumbered they must have lumbered	I must have been lumbering you must have been lumbering she must have been lumbering we must have been lumbering you must have been lumbering they must have been lumbering

Negation

Simple form	V-ing form
I mustn't lumber you mustn't lumber she mustn't lumber we mustn't lumber you mustn't lumber they mustn't lumber	I mustn't be lumbering you mustn't be lumbering she mustn't be lumbering we mustn't be lumbering you mustn't be lumbering they mustn't be lumbering
Perfect	V-ing perfect
I mustn't have lumbered you mustn't have lumbered she mustn't have lumbered we mustn't have lumbered you mustn't have lumbered they mustn't have lumbered	I mustn't have been lumbering you mustn't have been lumbering she mustn't have been lumbering we mustn't have been lumbering you mustn't have been lumbering they mustn't have been lumbering

Interrogative form

Simple form	V-ing form
must I lumber? must you lumber? must she lumber? must we lumber? must you lumber? must they lumber?	must I be lumbering? must you be lumbering? must she be lumbering? must we be lumbering? must you be lumbering? must they be lumbering?
Perfect	V-ing perfect
must I have lumbered? must you have lumbered? must she have lumbered? must we have lumbered? must you have lumbered? must they have lumbered?	must I have been lumbering? must you have been lumbering? must she have been lumbering? must we have been lumbering? must you have been lumbering? must they have been lumbering?

Interro-negative form

Simple form	V-ing form
mustn't I lumber? mustn't you lumber? mustn't she lumber? mustn't we lumber? mustn't you lumber? mustn't they lumber?	mustn't I be lumbering? mustn't you be lumbering? mustn't she be lumbering? mustn't we be lumbering? mustn't you be lumbering? mustn't they be lumbering?
Perfect	V-ing perfect
mustn't I have lumbered? mustn't you have lumbered? mustn't she have lumbered? mustn't we have lumbered? mustn't you have lumbered? mustn't they have lumbered?	mustn't I have been lumbering? mustn't you have been lumbering? mustn't she have been lumbering? mustn't we have been lumbering? mustn't you have been lumbering? mustn't they have been lumbering?