should thunder
Regular verb: thunder - thundered- thundered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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it'd thunder
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it'd be thundering
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it should've thundered
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it should've been thundering
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Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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it shouldn't thunder
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it shouldn't be thundering
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it shouldn't have thundered
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it shouldn't have been thundering
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Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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should it thunder?
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should it be thundering?
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should it have thundered?
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should it have been thundering?
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Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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shouldn't it thunder?
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shouldn't it be thundering?
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shouldn't it have thundered?
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shouldn't it have been thundering?
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