English verb conjugation
COULD HEAT

Regular verb: heat - heated - heated

Affirmation

Simple form	V-ing form
I could heat you could heat she could heat we could heat you could heat they could heat	I could be heating you could be heating she could be heating we could be heating you could be heating they could be heating
Perfect	V-ing perfect
I could have heated you could have heated she could have heated we could have heated you could have heated they could have heated	I could have been heating you could have been heating she could have been heating we could have been heating you could have been heating they could have been heating

Negation

Simple form	V-ing form
I couldn't heat you couldn't heat she couldn't heat we couldn't heat you couldn't heat they couldn't heat	I couldn't be heating you couldn't be heating she couldn't be heating we couldn't be heating you couldn't be heating they couldn't be heating
Perfect	V-ing perfect
I couldn't have heated you couldn't have heated she couldn't have heated we couldn't have heated you couldn't have heated they couldn't have heated	I couldn't have been heating you couldn't have been heating she couldn't have been heating we couldn't have been heating you couldn't have been heating they couldn't have been heating

Interrogative form

Simple form	V-ing form
could I heat? could you heat? could she heat? could we heat? could you heat? could they heat?	could I be heating? could you be heating? could she be heating? could we be heating? could you be heating? could they be heating?
Perfect	V-ing perfect
could I have heated? could you have heated? could she have heated? could we have heated? could you have heated? could they have heated?	could I have been heating? could you have been heating? could she have been heating? could we have been heating? could you have been heating? could they have been heating?

Interro-negative form

Simple form	V-ing form
couldn't I heat? couldn't you heat? couldn't she heat? couldn't we heat? couldn't you heat? couldn't they heat?	couldn't I be heating? couldn't you be heating? couldn't she be heating? couldn't we be heating? couldn't you be heating? couldn't they be heating?
Perfect	V-ing perfect
couldn't I have heated? couldn't you have heated? couldn't she have heated? couldn't we have heated? couldn't you have heated? couldn't they have heated?	couldn't I have been heating? couldn't you have been heating? couldn't she have been heating? couldn't we have been heating? couldn't you have been heating? couldn't they have been heating?