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 couldn't sparkle you couldn't sparkle he couldn't sparkle we couldn't sparkle you couldn't sparkle they couldn't sparkle	I couldn't be sparkling you couldn't be sparkling he couldn't be sparkling we couldn't be sparkling you couldn't be sparkling they couldn't be sparkling
Perfect	V-ing perfect
I couldn't have sparkled you couldn't have sparkled he couldn't have sparkled we couldn't have sparkled you couldn't have sparkled they couldn't have sparkled	I couldn't have been sparkling you couldn't have been sparkling he couldn't have been sparkling we couldn't have been sparkling you couldn't have been sparkling they couldn't 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
couldn't I sparkle? couldn't you sparkle? couldn't he sparkle? couldn't we sparkle? couldn't you sparkle? couldn't they sparkle?	couldn't I be sparkling? couldn't you be sparkling? couldn't he be sparkling? couldn't we be sparkling? couldn't you be sparkling? couldn't they be sparkling?
Perfect	V-ing perfect
couldn't I have sparkled? couldn't you have sparkled? couldn't he have sparkled? couldn't we have sparkled? couldn't you have sparkled? couldn't they have sparkled?	couldn't I have been sparkling? couldn't you have been sparkling? couldn't he have been sparkling? couldn't we have been sparkling? couldn't you have been sparkling? couldn't they have been sparkling?