must seem
Regular verb: seem - seemed- seemed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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it must seem
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it must be seeming
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it must have seemed
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it must have been seeming
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Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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it mustn't seem
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it mustn't be seeming
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it mustn't have seemed
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it mustn't have been seeming
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Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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must it seem?
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must it be seeming?
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must it have seemed?
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must it have been seeming?
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Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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mustn't it seem?
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mustn't it be seeming?
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mustn't it have seemed?
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mustn't it have been seeming?
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