English verb conjugation
COULD PREWORK

Regular verb: prework - preworked - preworked

Affirmation

Simple form	V-ing form
I could prework you could prework he could prework we could prework you could prework they could prework	I could be preworking you could be preworking he could be preworking we could be preworking you could be preworking they could be preworking
Perfect	V-ing perfect
I could have preworked you could have preworked he could have preworked we could have preworked you could have preworked they could have preworked	I could have been preworking you could have been preworking he could have been preworking we could have been preworking you could have been preworking they could have been preworking

Negation

Simple form	V-ing form
I couldn't prework you couldn't prework he couldn't prework we couldn't prework you couldn't prework they couldn't prework	I couldn't be preworking you couldn't be preworking he couldn't be preworking we couldn't be preworking you couldn't be preworking they couldn't be preworking
Perfect	V-ing perfect
I couldn't have preworked you couldn't have preworked he couldn't have preworked we couldn't have preworked you couldn't have preworked they couldn't have preworked	I couldn't have been preworking you couldn't have been preworking he couldn't have been preworking we couldn't have been preworking you couldn't have been preworking they couldn't have been preworking

Interrogative form

Simple form	V-ing form
could I prework? could you prework? could he prework? could we prework? could you prework? could they prework?	could I be preworking? could you be preworking? could he be preworking? could we be preworking? could you be preworking? could they be preworking?
Perfect	V-ing perfect
could I have preworked? could you have preworked? could he have preworked? could we have preworked? could you have preworked? could they have preworked?	could I have been preworking? could you have been preworking? could he have been preworking? could we have been preworking? could you have been preworking? could they have been preworking?

Interro-negative form

Simple form	V-ing form
couldn't I prework? couldn't you prework? couldn't he prework? couldn't we prework? couldn't you prework? couldn't they prework?	couldn't I be preworking? couldn't you be preworking? couldn't he be preworking? couldn't we be preworking? couldn't you be preworking? couldn't they be preworking?
Perfect	V-ing perfect
couldn't I have preworked? couldn't you have preworked? couldn't he have preworked? couldn't we have preworked? couldn't you have preworked? couldn't they have preworked?	couldn't I have been preworking? couldn't you have been preworking? couldn't he have been preworking? couldn't we have been preworking? couldn't you have been preworking? couldn't they have been preworking?