English verb conjugation
COULD STARTLE

Regular verb: startle - startled - startled

Affirmation

Simple form	V-ing form
I could startle you could startle he could startle we could startle you could startle they could startle	I could be startling you could be startling he could be startling we could be startling you could be startling they could be startling
Perfect	V-ing perfect
I could have startled you could have startled he could have startled we could have startled you could have startled they could have startled	I could have been startling you could have been startling he could have been startling we could have been startling you could have been startling they could have been startling

Negation

Simple form	V-ing form
I couldn't startle you couldn't startle he couldn't startle we couldn't startle you couldn't startle they couldn't startle	I couldn't be startling you couldn't be startling he couldn't be startling we couldn't be startling you couldn't be startling they couldn't be startling
Perfect	V-ing perfect
I couldn't have startled you couldn't have startled he couldn't have startled we couldn't have startled you couldn't have startled they couldn't have startled	I couldn't have been startling you couldn't have been startling he couldn't have been startling we couldn't have been startling you couldn't have been startling they couldn't have been startling

Interrogative form

Simple form	V-ing form
could I startle? could you startle? could he startle? could we startle? could you startle? could they startle?	could I be startling? could you be startling? could he be startling? could we be startling? could you be startling? could they be startling?
Perfect	V-ing perfect
could I have startled? could you have startled? could he have startled? could we have startled? could you have startled? could they have startled?	could I have been startling? could you have been startling? could he have been startling? could we have been startling? could you have been startling? could they have been startling?

Interro-negative form

Simple form	V-ing form
couldn't I startle? couldn't you startle? couldn't he startle? couldn't we startle? couldn't you startle? couldn't they startle?	couldn't I be startling? couldn't you be startling? couldn't he be startling? couldn't we be startling? couldn't you be startling? couldn't they be startling?
Perfect	V-ing perfect
couldn't I have startled? couldn't you have startled? couldn't he have startled? couldn't we have startled? couldn't you have startled? couldn't they have startled?	couldn't I have been startling? couldn't you have been startling? couldn't he have been startling? couldn't we have been startling? couldn't you have been startling? couldn't they have been startling?