to happen
Regular verb: happen - happened- happened

Indicative 	
Present 	Present continuous 	Preterite 	Preterite continuous 	
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it doesn't happen
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itisn't happening
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it didn't happen
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itwasn't happening
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Present perfect 	Present perfect continuous 	Pluperfect 	Pluperfect continuous 	
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it hasn't happened
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it hasn't  been happening
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it hadn't happened
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it hadn't been happening
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Future 	Future continuous 	Future perfect 	Future perfect continuous 	
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it won't happen
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it won't be happening
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it won't have happened
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it won't have been happening
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Conditional 	
Present 	Present continuous 	Past 	Past continuous 	
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it wouldn't happen
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it wouldn't be happening
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it wouldn't have happened
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it wouldn't have been happening
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Infinitive 	
Imperative 	
Infinitive 	 	Imperative 	 	
to happen 	 	-
Let's not happen
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Participle 	
Present 	Past 	 	 	
happening	happened