English verb conjugation
COULD SPUTTER

Regular verb: sputter - sputtered - sputtered

Affirmation

Simple form	V-ing form
I could sputter you could sputter she could sputter we could sputter you could sputter they could sputter	I could be sputtering you could be sputtering she could be sputtering we could be sputtering you could be sputtering they could be sputtering
Perfect	V-ing perfect
I could have sputtered you could have sputtered she could have sputtered we could have sputtered you could have sputtered they could have sputtered	I could have been sputtering you could have been sputtering she could have been sputtering we could have been sputtering you could have been sputtering they could have been sputtering

Negation

Simple form	V-ing form
I couldn't sputter you couldn't sputter she couldn't sputter we couldn't sputter you couldn't sputter they couldn't sputter	I couldn't be sputtering you couldn't be sputtering she couldn't be sputtering we couldn't be sputtering you couldn't be sputtering they couldn't be sputtering
Perfect	V-ing perfect
I couldn't have sputtered you couldn't have sputtered she couldn't have sputtered we couldn't have sputtered you couldn't have sputtered they couldn't have sputtered	I couldn't have been sputtering you couldn't have been sputtering she couldn't have been sputtering we couldn't have been sputtering you couldn't have been sputtering they couldn't have been sputtering

Interrogative form

Simple form	V-ing form
could I sputter? could you sputter? could she sputter? could we sputter? could you sputter? could they sputter?	could I be sputtering? could you be sputtering? could she be sputtering? could we be sputtering? could you be sputtering? could they be sputtering?
Perfect	V-ing perfect
could I have sputtered? could you have sputtered? could she have sputtered? could we have sputtered? could you have sputtered? could they have sputtered?	could I have been sputtering? could you have been sputtering? could she have been sputtering? could we have been sputtering? could you have been sputtering? could they have been sputtering?

Interro-negative form

Simple form	V-ing form
couldn't I sputter? couldn't you sputter? couldn't she sputter? couldn't we sputter? couldn't you sputter? couldn't they sputter?	couldn't I be sputtering? couldn't you be sputtering? couldn't she be sputtering? couldn't we be sputtering? couldn't you be sputtering? couldn't they be sputtering?
Perfect	V-ing perfect
couldn't I have sputtered? couldn't you have sputtered? couldn't she have sputtered? couldn't we have sputtered? couldn't you have sputtered? couldn't they have sputtered?	couldn't I have been sputtering? couldn't you have been sputtering? couldn't she have been sputtering? couldn't we have been sputtering? couldn't you have been sputtering? couldn't they have been sputtering?