Conjugación del verbo inglés COULD HAPPEN
Verbo regular: happen - happened - happened
Afirmación
Forma simple
--
it could happen
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Forma con V-ing
--
it could be happening
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Perfecto
--
it could have happened
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Perfecto con V-ing
--
it could have been happening
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Negación
Forma simple
--
it could not happen
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Forma con V-ing
--
it could not be happening
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Perfecto
--
it could not have happened
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Perfecto con V-ing
--
it could not have been happening
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Forma interrogativa
Forma simple
--
could it happen?
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Forma con V-ing
--
could it be happening?
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Perfecto
--
could it have happened?
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Perfecto con V-ing
--
could it have been happening?
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Forma interro-negativa
Forma simple
--
could it not happen?
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Forma con V-ing
--
could it not be happening?
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Perfecto
--
could it not have happened?
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Perfecto con V-ing
--
could it not have been happening?
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