English verb conjugation
COULD PIGGYBACK

Regular verb: piggyback - piggybacked - piggybacked

Affirmation

Simple form	V-ing form
I could piggyback you could piggyback he could piggyback we could piggyback you could piggyback they could piggyback	I could be piggybacking you could be piggybacking he could be piggybacking we could be piggybacking you could be piggybacking they could be piggybacking
Perfect	V-ing perfect
I could have piggybacked you could have piggybacked he could have piggybacked we could have piggybacked you could have piggybacked they could have piggybacked	I could have been piggybacking you could have been piggybacking he could have been piggybacking we could have been piggybacking you could have been piggybacking they could have been piggybacking

Negation

Simple form	V-ing form
I couldn't piggyback you couldn't piggyback he couldn't piggyback we couldn't piggyback you couldn't piggyback they couldn't piggyback	I couldn't be piggybacking you couldn't be piggybacking he couldn't be piggybacking we couldn't be piggybacking you couldn't be piggybacking they couldn't be piggybacking
Perfect	V-ing perfect
I couldn't have piggybacked you couldn't have piggybacked he couldn't have piggybacked we couldn't have piggybacked you couldn't have piggybacked they couldn't have piggybacked	I couldn't have been piggybacking you couldn't have been piggybacking he couldn't have been piggybacking we couldn't have been piggybacking you couldn't have been piggybacking they couldn't have been piggybacking

Interrogative form

Simple form	V-ing form
could I piggyback? could you piggyback? could he piggyback? could we piggyback? could you piggyback? could they piggyback?	could I be piggybacking? could you be piggybacking? could he be piggybacking? could we be piggybacking? could you be piggybacking? could they be piggybacking?
Perfect	V-ing perfect
could I have piggybacked? could you have piggybacked? could he have piggybacked? could we have piggybacked? could you have piggybacked? could they have piggybacked?	could I have been piggybacking? could you have been piggybacking? could he have been piggybacking? could we have been piggybacking? could you have been piggybacking? could they have been piggybacking?

Interro-negative form

Simple form	V-ing form
couldn't I piggyback? couldn't you piggyback? couldn't he piggyback? couldn't we piggyback? couldn't you piggyback? couldn't they piggyback?	couldn't I be piggybacking? couldn't you be piggybacking? couldn't he be piggybacking? couldn't we be piggybacking? couldn't you be piggybacking? couldn't they be piggybacking?
Perfect	V-ing perfect
couldn't I have piggybacked? couldn't you have piggybacked? couldn't he have piggybacked? couldn't we have piggybacked? couldn't you have piggybacked? couldn't they have piggybacked?	couldn't I have been piggybacking? couldn't you have been piggybacking? couldn't he have been piggybacking? couldn't we have been piggybacking? couldn't you have been piggybacking? couldn't they have been piggybacking?