English verb conjugation
COULD TIMBER

Regular verb: timber - timbered - timbered

Affirmation

Simple form	V-ing form
I could timber you could timber he could timber we could timber you could timber they could timber	I could be timbering you could be timbering he could be timbering we could be timbering you could be timbering they could be timbering
Perfect	V-ing perfect
I could have timbered you could have timbered he could have timbered we could have timbered you could have timbered they could have timbered	I could have been timbering you could have been timbering he could have been timbering we could have been timbering you could have been timbering they could have been timbering

Negation

Simple form	V-ing form
I couldn't timber you couldn't timber he couldn't timber we couldn't timber you couldn't timber they couldn't timber	I couldn't be timbering you couldn't be timbering he couldn't be timbering we couldn't be timbering you couldn't be timbering they couldn't be timbering
Perfect	V-ing perfect
I couldn't have timbered you couldn't have timbered he couldn't have timbered we couldn't have timbered you couldn't have timbered they couldn't have timbered	I couldn't have been timbering you couldn't have been timbering he couldn't have been timbering we couldn't have been timbering you couldn't have been timbering they couldn't have been timbering

Interrogative form

Simple form	V-ing form
could I timber? could you timber? could he timber? could we timber? could you timber? could they timber?	could I be timbering? could you be timbering? could he be timbering? could we be timbering? could you be timbering? could they be timbering?
Perfect	V-ing perfect
could I have timbered? could you have timbered? could he have timbered? could we have timbered? could you have timbered? could they have timbered?	could I have been timbering? could you have been timbering? could he have been timbering? could we have been timbering? could you have been timbering? could they have been timbering?

Interro-negative form

Simple form	V-ing form
couldn't I timber? couldn't you timber? couldn't he timber? couldn't we timber? couldn't you timber? couldn't they timber?	couldn't I be timbering? couldn't you be timbering? couldn't he be timbering? couldn't we be timbering? couldn't you be timbering? couldn't they be timbering?
Perfect	V-ing perfect
couldn't I have timbered? couldn't you have timbered? couldn't he have timbered? couldn't we have timbered? couldn't you have timbered? couldn't they have timbered?	couldn't I have been timbering? couldn't you have been timbering? couldn't he have been timbering? couldn't we have been timbering? couldn't you have been timbering? couldn't they have been timbering?