could overstaff
Regular verb: overstaff - overstaffed- overstaffed

Affirmation 	
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I could overstaff
you could overstaff
she could overstaff
we could overstaff
you could overstaff
they could overstaff 	I could be overstaffing
you could be overstaffing
she could be overstaffing
we could be overstaffing
you could be overstaffing
they could be overstaffing	I could have overstaffed
you could have overstaffed
she could have overstaffed
we could have overstaffed
you could have overstaffed
they could have overstaffed	I could have been overstaffing
you could have been overstaffing
she could have been overstaffing
we could have been overstaffing
you could have been overstaffing
they could have been overstaffing	

Negation 	
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I couldn't overstaff
you couldn't overstaff
she couldn't overstaff
we couldn't overstaff
you couldn't overstaff
they couldn't overstaff 	I couldn't be overstaffing
you couldn't be overstaffing
she couldn't be overstaffing
we couldn't be overstaffing
you couldn't be overstaffing
they couldn't be overstaffing	I couldn't have overstaffed
you couldn't have overstaffed
she couldn't have overstaffed
we couldn't have overstaffed
you couldn't have overstaffed
they couldn't have overstaffed	I couldn't have been overstaffing
you couldn't have been overstaffing
she couldn't have been overstaffing
we couldn't have been overstaffing
you couldn't have been overstaffing
they couldn't have been overstaffing	

Interrogative form 	
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could I overstaff?
could you overstaff?
could she overstaff?
could we overstaff?
could you overstaff?
could they overstaff? 	could I be overstaffing?
could you be overstaffing?
could she be overstaffing?
could we be overstaffing?
could you be overstaffing?
could they be overstaffing? 	could I have overstaffed?
could you have overstaffed?
could she have overstaffed?
could we have overstaffed?
could you have overstaffed?
could they have overstaffed? 	could I have been overstaffing?
could you have been overstaffing?
could she have been overstaffing?
could we have been overstaffing?
could you have been overstaffing?
could they have been overstaffing? 	

Interro-negative form 	
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couldn't I overstaff?
couldn't you overstaff?
couldn't she overstaff?
couldn't we overstaff?
couldn't you overstaff?
couldn't they overstaff? 	couldn't I be overstaffing?
couldn't you be overstaffing?
couldn't she be overstaffing?
couldn't we be overstaffing?
couldn't you be overstaffing?
couldn't they be overstaffing? 	couldn't I have overstaffed?
couldn't you have overstaffed?
couldn't she have overstaffed?
couldn't we have overstaffed?
couldn't you have overstaffed?
couldn't they have overstaffed? 	couldn't I have been overstaffing?
couldn't you have been overstaffing?
couldn't she have been overstaffing?
couldn't we have been overstaffing?
couldn't you have been overstaffing?
couldn't they have been overstaffing?