English verb conjugation
COULD PLANE

Regular verb: plane - planed - planed

Affirmation

Simple form	V-ing form
I could plane you could plane she could plane we could plane you could plane they could plane	I could be planing you could be planing she could be planing we could be planing you could be planing they could be planing
Perfect	V-ing perfect
I could have planed you could have planed she could have planed we could have planed you could have planed they could have planed	I could have been planing you could have been planing she could have been planing we could have been planing you could have been planing they could have been planing

Negation

Simple form	V-ing form
I couldn't plane you couldn't plane she couldn't plane we couldn't plane you couldn't plane they couldn't plane	I couldn't be planing you couldn't be planing she couldn't be planing we couldn't be planing you couldn't be planing they couldn't be planing
Perfect	V-ing perfect
I couldn't have planed you couldn't have planed she couldn't have planed we couldn't have planed you couldn't have planed they couldn't have planed	I couldn't have been planing you couldn't have been planing she couldn't have been planing we couldn't have been planing you couldn't have been planing they couldn't have been planing

Interrogative form

Simple form	V-ing form
could I plane? could you plane? could she plane? could we plane? could you plane? could they plane?	could I be planing? could you be planing? could she be planing? could we be planing? could you be planing? could they be planing?
Perfect	V-ing perfect
could I have planed? could you have planed? could she have planed? could we have planed? could you have planed? could they have planed?	could I have been planing? could you have been planing? could she have been planing? could we have been planing? could you have been planing? could they have been planing?

Interro-negative form

Simple form	V-ing form
couldn't I plane? couldn't you plane? couldn't she plane? couldn't we plane? couldn't you plane? couldn't they plane?	couldn't I be planing? couldn't you be planing? couldn't she be planing? couldn't we be planing? couldn't you be planing? couldn't they be planing?
Perfect	V-ing perfect
couldn't I have planed? couldn't you have planed? couldn't she have planed? couldn't we have planed? couldn't you have planed? couldn't they have planed?	couldn't I have been planing? couldn't you have been planing? couldn't she have been planing? couldn't we have been planing? couldn't you have been planing? couldn't they have been planing?