English verb conjugation
COULD LUMBER

Regular verb: lumber - lumbered - lumbered

Affirmation

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

Negation

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

Interrogative form

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

Interro-negative form

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