could backfire
Regular verb: backfire - backfired- backfired

Affirmation 	
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I could backfire
you could backfire
she could backfire
we could backfire
you could backfire
they could backfire 	I could be backfiring
you could be backfiring
she could be backfiring
we could be backfiring
you could be backfiring
they could be backfiring	I could have backfired
you could have backfired
she could have backfired
we could have backfired
you could have backfired
they could have backfired	I could have been backfiring
you could have been backfiring
she could have been backfiring
we could have been backfiring
you could have been backfiring
they could have been backfiring	

Negation 	
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I couldn't backfire
you couldn't backfire
she couldn't backfire
we couldn't backfire
you couldn't backfire
they couldn't backfire 	I couldn't be backfiring
you couldn't be backfiring
she couldn't be backfiring
we couldn't be backfiring
you couldn't be backfiring
they couldn't be backfiring	I couldn't have backfired
you couldn't have backfired
she couldn't have backfired
we couldn't have backfired
you couldn't have backfired
they couldn't have backfired	I couldn't have been backfiring
you couldn't have been backfiring
she couldn't have been backfiring
we couldn't have been backfiring
you couldn't have been backfiring
they couldn't have been backfiring	

Interrogative form 	
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could I backfire?
could you backfire?
could she backfire?
could we backfire?
could you backfire?
could they backfire? 	could I be backfiring?
could you be backfiring?
could she be backfiring?
could we be backfiring?
could you be backfiring?
could they be backfiring? 	could I have backfired?
could you have backfired?
could she have backfired?
could we have backfired?
could you have backfired?
could they have backfired? 	could I have been backfiring?
could you have been backfiring?
could she have been backfiring?
could we have been backfiring?
could you have been backfiring?
could they have been backfiring? 	

Interro-negative form 	
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couldn't I backfire?
couldn't you backfire?
couldn't she backfire?
couldn't we backfire?
couldn't you backfire?
couldn't they backfire? 	couldn't I be backfiring?
couldn't you be backfiring?
couldn't she be backfiring?
couldn't we be backfiring?
couldn't you be backfiring?
couldn't they be backfiring? 	couldn't I have backfired?
couldn't you have backfired?
couldn't she have backfired?
couldn't we have backfired?
couldn't you have backfired?
couldn't they have backfired? 	couldn't I have been backfiring?
couldn't you have been backfiring?
couldn't she have been backfiring?
couldn't we have been backfiring?
couldn't you have been backfiring?
couldn't they have been backfiring?