English verb conjugation
COULD TISSUE

Regular verb: tissue - tissued - tissued

Affirmation

Simple form	V-ing form
I could tissue you could tissue she could tissue we could tissue you could tissue they could tissue	I could be tissuing you could be tissuing she could be tissuing we could be tissuing you could be tissuing they could be tissuing
Perfect	V-ing perfect
I could have tissued you could have tissued she could have tissued we could have tissued you could have tissued they could have tissued	I could have been tissuing you could have been tissuing she could have been tissuing we could have been tissuing you could have been tissuing they could have been tissuing

Negation

Simple form	V-ing form
I couldn't tissue you couldn't tissue she couldn't tissue we couldn't tissue you couldn't tissue they couldn't tissue	I couldn't be tissuing you couldn't be tissuing she couldn't be tissuing we couldn't be tissuing you couldn't be tissuing they couldn't be tissuing
Perfect	V-ing perfect
I couldn't have tissued you couldn't have tissued she couldn't have tissued we couldn't have tissued you couldn't have tissued they couldn't have tissued	I couldn't have been tissuing you couldn't have been tissuing she couldn't have been tissuing we couldn't have been tissuing you couldn't have been tissuing they couldn't have been tissuing

Interrogative form

Simple form	V-ing form
could I tissue? could you tissue? could she tissue? could we tissue? could you tissue? could they tissue?	could I be tissuing? could you be tissuing? could she be tissuing? could we be tissuing? could you be tissuing? could they be tissuing?
Perfect	V-ing perfect
could I have tissued? could you have tissued? could she have tissued? could we have tissued? could you have tissued? could they have tissued?	could I have been tissuing? could you have been tissuing? could she have been tissuing? could we have been tissuing? could you have been tissuing? could they have been tissuing?

Interro-negative form

Simple form	V-ing form
couldn't I tissue? couldn't you tissue? couldn't she tissue? couldn't we tissue? couldn't you tissue? couldn't they tissue?	couldn't I be tissuing? couldn't you be tissuing? couldn't she be tissuing? couldn't we be tissuing? couldn't you be tissuing? couldn't they be tissuing?
Perfect	V-ing perfect
couldn't I have tissued? couldn't you have tissued? couldn't she have tissued? couldn't we have tissued? couldn't you have tissued? couldn't they have tissued?	couldn't I have been tissuing? couldn't you have been tissuing? couldn't she have been tissuing? couldn't we have been tissuing? couldn't you have been tissuing? couldn't they have been tissuing?