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 mightn't happen
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it mightn't be happening
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it mightn't have happened
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it mightn't 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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mightn't it happen?
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mightn't it be happening?
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mightn't it have happened?
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mightn't it have been happening?
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