could quarantine
Regular verb: quarantine - quarantined- quarantined

Affirmation 	
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I could quarantine
you could quarantine
she could quarantine
we could quarantine
you could quarantine
they could quarantine 	I could be quarantining
you could be quarantining
she could be quarantining
we could be quarantining
you could be quarantining
they could be quarantining	I could have quarantined
you could have quarantined
she could have quarantined
we could have quarantined
you could have quarantined
they could have quarantined	I could have been quarantining
you could have been quarantining
she could have been quarantining
we could have been quarantining
you could have been quarantining
they could have been quarantining	

Negation 	
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I couldn't quarantine
you couldn't quarantine
she couldn't quarantine
we couldn't quarantine
you couldn't quarantine
they couldn't quarantine 	I couldn't be quarantining
you couldn't be quarantining
she couldn't be quarantining
we couldn't be quarantining
you couldn't be quarantining
they couldn't be quarantining	I couldn't have quarantined
you couldn't have quarantined
she couldn't have quarantined
we couldn't have quarantined
you couldn't have quarantined
they couldn't have quarantined	I couldn't have been quarantining
you couldn't have been quarantining
she couldn't have been quarantining
we couldn't have been quarantining
you couldn't have been quarantining
they couldn't have been quarantining	

Interrogative form 	
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could I quarantine?
could you quarantine?
could she quarantine?
could we quarantine?
could you quarantine?
could they quarantine? 	could I be quarantining?
could you be quarantining?
could she be quarantining?
could we be quarantining?
could you be quarantining?
could they be quarantining? 	could I have quarantined?
could you have quarantined?
could she have quarantined?
could we have quarantined?
could you have quarantined?
could they have quarantined? 	could I have been quarantining?
could you have been quarantining?
could she have been quarantining?
could we have been quarantining?
could you have been quarantining?
could they have been quarantining? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I quarantine?
couldn't you quarantine?
couldn't she quarantine?
couldn't we quarantine?
couldn't you quarantine?
couldn't they quarantine? 	couldn't I be quarantining?
couldn't you be quarantining?
couldn't she be quarantining?
couldn't we be quarantining?
couldn't you be quarantining?
couldn't they be quarantining? 	couldn't I have quarantined?
couldn't you have quarantined?
couldn't she have quarantined?
couldn't we have quarantined?
couldn't you have quarantined?
couldn't they have quarantined? 	couldn't I have been quarantining?
couldn't you have been quarantining?
couldn't she have been quarantining?
couldn't we have been quarantining?
couldn't you have been quarantining?
couldn't they have been quarantining?