English verb conjugation
COULD SPARKLE

Regular verb: sparkle - sparkled - sparkled

Affirmation

Simple form	V-ing form
I could sparkle you could sparkle he could sparkle we could sparkle you could sparkle they could sparkle	I could be sparkling you could be sparkling he could be sparkling we could be sparkling you could be sparkling they could be sparkling
Perfect	V-ing perfect
I could have sparkled you could have sparkled he could have sparkled we could have sparkled you could have sparkled they could have sparkled	I could have been sparkling you could have been sparkling he could have been sparkling we could have been sparkling you could have been sparkling they could have been sparkling

Negation

Simple form	V-ing form
I could not sparkle you could not sparkle he could not sparkle we could not sparkle you could not sparkle they could not sparkle	I could not be sparkling you could not be sparkling he could not be sparkling we could not be sparkling you could not be sparkling they could not be sparkling
Perfect	V-ing perfect
I could not have sparkled you could not have sparkled he could not have sparkled we could not have sparkled you could not have sparkled they could not have sparkled	I could not have been sparkling you could not have been sparkling he could not have been sparkling we could not have been sparkling you could not have been sparkling they could not have been sparkling

Interrogative form

Simple form	V-ing form
could I sparkle? could you sparkle? could he sparkle? could we sparkle? could you sparkle? could they sparkle?	could I be sparkling? could you be sparkling? could he be sparkling? could we be sparkling? could you be sparkling? could they be sparkling?
Perfect	V-ing perfect
could I have sparkled? could you have sparkled? could he have sparkled? could we have sparkled? could you have sparkled? could they have sparkled?	could I have been sparkling? could you have been sparkling? could he have been sparkling? could we have been sparkling? could you have been sparkling? could they have been sparkling?

Interro-negative form

Simple form	V-ing form
could I not sparkle? could you not sparkle? could he not sparkle? could we not sparkle? could you not sparkle? could they not sparkle?	could I not be sparkling? could you not be sparkling? could he not be sparkling? could we not be sparkling? could you not be sparkling? could they not be sparkling?
Perfect	V-ing perfect
could I not have sparkled? could you not have sparkled? could he not have sparkled? could we not have sparkled? could you not have sparkled? could they not have sparkled?	could I not have been sparkling? could you not have been sparkling? could he not have been sparkling? could we not have been sparkling? could you not have been sparkling? could they not have been sparkling?