English verb conjugation
COULD SNIFFLE

Regular verb: sniffle - sniffled - sniffled

Affirmation

Simple form	V-ing form
I could sniffle you could sniffle he could sniffle we could sniffle you could sniffle they could sniffle	I could be sniffling you could be sniffling he could be sniffling we could be sniffling you could be sniffling they could be sniffling
Perfect	V-ing perfect
I could have sniffled you could have sniffled he could have sniffled we could have sniffled you could have sniffled they could have sniffled	I could have been sniffling you could have been sniffling he could have been sniffling we could have been sniffling you could have been sniffling they could have been sniffling

Negation

Simple form	V-ing form
I could not sniffle you could not sniffle he could not sniffle we could not sniffle you could not sniffle they could not sniffle	I could not be sniffling you could not be sniffling he could not be sniffling we could not be sniffling you could not be sniffling they could not be sniffling
Perfect	V-ing perfect
I could not have sniffled you could not have sniffled he could not have sniffled we could not have sniffled you could not have sniffled they could not have sniffled	I could not have been sniffling you could not have been sniffling he could not have been sniffling we could not have been sniffling you could not have been sniffling they could not have been sniffling

Interrogative form

Simple form	V-ing form
could I sniffle? could you sniffle? could he sniffle? could we sniffle? could you sniffle? could they sniffle?	could I be sniffling? could you be sniffling? could he be sniffling? could we be sniffling? could you be sniffling? could they be sniffling?
Perfect	V-ing perfect
could I have sniffled? could you have sniffled? could he have sniffled? could we have sniffled? could you have sniffled? could they have sniffled?	could I have been sniffling? could you have been sniffling? could he have been sniffling? could we have been sniffling? could you have been sniffling? could they have been sniffling?

Interro-negative form

Simple form	V-ing form
could I not sniffle? could you not sniffle? could he not sniffle? could we not sniffle? could you not sniffle? could they not sniffle?	could I not be sniffling? could you not be sniffling? could he not be sniffling? could we not be sniffling? could you not be sniffling? could they not be sniffling?
Perfect	V-ing perfect
could I not have sniffled? could you not have sniffled? could he not have sniffled? could we not have sniffled? could you not have sniffled? could they not have sniffled?	could I not have been sniffling? could you not have been sniffling? could he not have been sniffling? could we not have been sniffling? could you not have been sniffling? could they not have been sniffling?