might happen
Regular verb: happen - happened- happened

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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it might happen
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it might be happening
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it might have happened
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it might have been happening
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Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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it might not happen
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it might not be happening
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it might not have happened
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it might not have been happening
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Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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might it happen?
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might it be happening?
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might it have happened?
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might it have been happening?
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Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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might it not happen?
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might it not be happening?
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might it not have happened?
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might it not have been happening?
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