English verb conjugation MAY HAPPEN

Regular verb: happen - happened - happened

Affirmation

Simple form

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it may happen
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V-ing form

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it may be happening
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Perfect

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it may have happened
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V-ing perfect

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it may have been happening
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Simple form

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it mayn't happen
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V-ing form

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it mayn't be happening
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Perfect

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it mayn't have happened
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V-ing perfect

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it mayn't have been happening
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Simple form

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may it happen?
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V-ing form

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may it be happening?
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Perfect

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may it have happened?
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V-ing perfect

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may it have been happening?
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Simple form

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mayn't it happen?
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V-ing form

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mayn't it be happening?
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Perfect

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mayn't it have happened?
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V-ing perfect

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mayn't it have been happening?
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