English verb conjugation
COULD STAGNATE

Regular verb: stagnate - stagnated - stagnated

Affirmation

Simple form	V-ing form
I could stagnate you could stagnate he could stagnate we could stagnate you could stagnate they could stagnate	I could be stagnating you could be stagnating he could be stagnating we could be stagnating you could be stagnating they could be stagnating
Perfect	V-ing perfect
I could have stagnated you could have stagnated he could have stagnated we could have stagnated you could have stagnated they could have stagnated	I could have been stagnating you could have been stagnating he could have been stagnating we could have been stagnating you could have been stagnating they could have been stagnating

Negation

Simple form	V-ing form
I couldn't stagnate you couldn't stagnate he couldn't stagnate we couldn't stagnate you couldn't stagnate they couldn't stagnate	I couldn't be stagnating you couldn't be stagnating he couldn't be stagnating we couldn't be stagnating you couldn't be stagnating they couldn't be stagnating
Perfect	V-ing perfect
I couldn't have stagnated you couldn't have stagnated he couldn't have stagnated we couldn't have stagnated you couldn't have stagnated they couldn't have stagnated	I couldn't have been stagnating you couldn't have been stagnating he couldn't have been stagnating we couldn't have been stagnating you couldn't have been stagnating they couldn't have been stagnating

Interrogative form

Simple form	V-ing form
could I stagnate? could you stagnate? could he stagnate? could we stagnate? could you stagnate? could they stagnate?	could I be stagnating? could you be stagnating? could he be stagnating? could we be stagnating? could you be stagnating? could they be stagnating?
Perfect	V-ing perfect
could I have stagnated? could you have stagnated? could he have stagnated? could we have stagnated? could you have stagnated? could they have stagnated?	could I have been stagnating? could you have been stagnating? could he have been stagnating? could we have been stagnating? could you have been stagnating? could they have been stagnating?

Interro-negative form

Simple form	V-ing form
couldn't I stagnate? couldn't you stagnate? couldn't he stagnate? couldn't we stagnate? couldn't you stagnate? couldn't they stagnate?	couldn't I be stagnating? couldn't you be stagnating? couldn't he be stagnating? couldn't we be stagnating? couldn't you be stagnating? couldn't they be stagnating?
Perfect	V-ing perfect
couldn't I have stagnated? couldn't you have stagnated? couldn't he have stagnated? couldn't we have stagnated? couldn't you have stagnated? couldn't they have stagnated?	couldn't I have been stagnating? couldn't you have been stagnating? couldn't he have been stagnating? couldn't we have been stagnating? couldn't you have been stagnating? couldn't they have been stagnating?