English verb conjugation
COULD PREINSTRUCT

Regular verb: preinstruct - preinstructed - preinstructed

Affirmation

Simple form	V-ing form
I could preinstruct you could preinstruct he could preinstruct we could preinstruct you could preinstruct they could preinstruct	I could be preinstructing you could be preinstructing he could be preinstructing we could be preinstructing you could be preinstructing they could be preinstructing
Perfect	V-ing perfect
I could have preinstructed you could have preinstructed he could have preinstructed we could have preinstructed you could have preinstructed they could have preinstructed	I could have been preinstructing you could have been preinstructing he could have been preinstructing we could have been preinstructing you could have been preinstructing they could have been preinstructing

Negation

Simple form	V-ing form
I couldn't preinstruct you couldn't preinstruct he couldn't preinstruct we couldn't preinstruct you couldn't preinstruct they couldn't preinstruct	I couldn't be preinstructing you couldn't be preinstructing he couldn't be preinstructing we couldn't be preinstructing you couldn't be preinstructing they couldn't be preinstructing
Perfect	V-ing perfect
I couldn't have preinstructed you couldn't have preinstructed he couldn't have preinstructed we couldn't have preinstructed you couldn't have preinstructed they couldn't have preinstructed	I couldn't have been preinstructing you couldn't have been preinstructing he couldn't have been preinstructing we couldn't have been preinstructing you couldn't have been preinstructing they couldn't have been preinstructing

Interrogative form

Simple form	V-ing form
could I preinstruct? could you preinstruct? could he preinstruct? could we preinstruct? could you preinstruct? could they preinstruct?	could I be preinstructing? could you be preinstructing? could he be preinstructing? could we be preinstructing? could you be preinstructing? could they be preinstructing?
Perfect	V-ing perfect
could I have preinstructed? could you have preinstructed? could he have preinstructed? could we have preinstructed? could you have preinstructed? could they have preinstructed?	could I have been preinstructing? could you have been preinstructing? could he have been preinstructing? could we have been preinstructing? could you have been preinstructing? could they have been preinstructing?

Interro-negative form

Simple form	V-ing form
couldn't I preinstruct? couldn't you preinstruct? couldn't he preinstruct? couldn't we preinstruct? couldn't you preinstruct? couldn't they preinstruct?	couldn't I be preinstructing? couldn't you be preinstructing? couldn't he be preinstructing? couldn't we be preinstructing? couldn't you be preinstructing? couldn't they be preinstructing?
Perfect	V-ing perfect
couldn't I have preinstructed? couldn't you have preinstructed? couldn't he have preinstructed? couldn't we have preinstructed? couldn't you have preinstructed? couldn't they have preinstructed?	couldn't I have been preinstructing? couldn't you have been preinstructing? couldn't he have been preinstructing? couldn't we have been preinstructing? couldn't you have been preinstructing? couldn't they have been preinstructing?