could linger
Regular verb: linger - lingered- lingered

Affirmation 	
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I could linger
you could linger
he could linger
we could linger
you could linger
they could linger 	I could be lingering
you could be lingering
he could be lingering
we could be lingering
you could be lingering
they could be lingering	I could have lingered
you could have lingered
he could have lingered
we could have lingered
you could have lingered
they could have lingered	I could have been lingering
you could have been lingering
he could have been lingering
we could have been lingering
you could have been lingering
they could have been lingering	

Negation 	
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I couldn't linger
you couldn't linger
he couldn't linger
we couldn't linger
you couldn't linger
they couldn't linger 	I couldn't be lingering
you couldn't be lingering
he couldn't be lingering
we couldn't be lingering
you couldn't be lingering
they couldn't be lingering	I couldn't have lingered
you couldn't have lingered
he couldn't have lingered
we couldn't have lingered
you couldn't have lingered
they couldn't have lingered	I couldn't have been lingering
you couldn't have been lingering
he couldn't have been lingering
we couldn't have been lingering
you couldn't have been lingering
they couldn't have been lingering	

Interrogative form 	
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could I linger?
could you linger?
could he linger?
could we linger?
could you linger?
could they linger? 	could I be lingering?
could you be lingering?
could he be lingering?
could we be lingering?
could you be lingering?
could they be lingering? 	could I have lingered?
could you have lingered?
could he have lingered?
could we have lingered?
could you have lingered?
could they have lingered? 	could I have been lingering?
could you have been lingering?
could he have been lingering?
could we have been lingering?
could you have been lingering?
could they have been lingering? 	

Interro-negative form 	
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couldn't I linger?
couldn't you linger?
couldn't he linger?
couldn't we linger?
couldn't you linger?
couldn't they linger? 	couldn't I be lingering?
couldn't you be lingering?
couldn't he be lingering?
couldn't we be lingering?
couldn't you be lingering?
couldn't they be lingering? 	couldn't I have lingered?
couldn't you have lingered?
couldn't he have lingered?
couldn't we have lingered?
couldn't you have lingered?
couldn't they have lingered? 	couldn't I have been lingering?
couldn't you have been lingering?
couldn't he have been lingering?
couldn't we have been lingering?
couldn't you have been lingering?
couldn't they have been lingering?