English verb conjugation
COULD VOUCH

Regular verb: vouch - vouched - vouched

Affirmation

Simple form	V-ing form
I could vouch you could vouch she could vouch we could vouch you could vouch they could vouch	I could be vouching you could be vouching she could be vouching we could be vouching you could be vouching they could be vouching
Perfect	V-ing perfect
I could have vouched you could have vouched she could have vouched we could have vouched you could have vouched they could have vouched	I could have been vouching you could have been vouching she could have been vouching we could have been vouching you could have been vouching they could have been vouching

Negation

Simple form	V-ing form
I couldn't vouch you couldn't vouch she couldn't vouch we couldn't vouch you couldn't vouch they couldn't vouch	I couldn't be vouching you couldn't be vouching she couldn't be vouching we couldn't be vouching you couldn't be vouching they couldn't be vouching
Perfect	V-ing perfect
I couldn't have vouched you couldn't have vouched she couldn't have vouched we couldn't have vouched you couldn't have vouched they couldn't have vouched	I couldn't have been vouching you couldn't have been vouching she couldn't have been vouching we couldn't have been vouching you couldn't have been vouching they couldn't have been vouching

Interrogative form

Simple form	V-ing form
could I vouch? could you vouch? could she vouch? could we vouch? could you vouch? could they vouch?	could I be vouching? could you be vouching? could she be vouching? could we be vouching? could you be vouching? could they be vouching?
Perfect	V-ing perfect
could I have vouched? could you have vouched? could she have vouched? could we have vouched? could you have vouched? could they have vouched?	could I have been vouching? could you have been vouching? could she have been vouching? could we have been vouching? could you have been vouching? could they have been vouching?

Interro-negative form

Simple form	V-ing form
couldn't I vouch? couldn't you vouch? couldn't she vouch? couldn't we vouch? couldn't you vouch? couldn't they vouch?	couldn't I be vouching? couldn't you be vouching? couldn't she be vouching? couldn't we be vouching? couldn't you be vouching? couldn't they be vouching?
Perfect	V-ing perfect
couldn't I have vouched? couldn't you have vouched? couldn't she have vouched? couldn't we have vouched? couldn't you have vouched? couldn't they have vouched?	couldn't I have been vouching? couldn't you have been vouching? couldn't she have been vouching? couldn't we have been vouching? couldn't you have been vouching? couldn't they have been vouching?