could best
Regular verb: best - bested- bested

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could best
you could best
she could best
we could best
you could best
they could best 	I could be besting
you could be besting
she could be besting
we could be besting
you could be besting
they could be besting	I could have bested
you could have bested
she could have bested
we could have bested
you could have bested
they could have bested	I could have been besting
you could have been besting
she could have been besting
we could have been besting
you could have been besting
they could have been besting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't best
you couldn't best
she couldn't best
we couldn't best
you couldn't best
they couldn't best 	I couldn't be besting
you couldn't be besting
she couldn't be besting
we couldn't be besting
you couldn't be besting
they couldn't be besting	I couldn't have bested
you couldn't have bested
she couldn't have bested
we couldn't have bested
you couldn't have bested
they couldn't have bested	I couldn't have been besting
you couldn't have been besting
she couldn't have been besting
we couldn't have been besting
you couldn't have been besting
they couldn't have been besting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I best?
could you best?
could she best?
could we best?
could you best?
could they best? 	could I be besting?
could you be besting?
could she be besting?
could we be besting?
could you be besting?
could they be besting? 	could I have bested?
could you have bested?
could she have bested?
could we have bested?
could you have bested?
could they have bested? 	could I have been besting?
could you have been besting?
could she have been besting?
could we have been besting?
could you have been besting?
could they have been besting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I best?
couldn't you best?
couldn't she best?
couldn't we best?
couldn't you best?
couldn't they best? 	couldn't I be besting?
couldn't you be besting?
couldn't she be besting?
couldn't we be besting?
couldn't you be besting?
couldn't they be besting? 	couldn't I have bested?
couldn't you have bested?
couldn't she have bested?
couldn't we have bested?
couldn't you have bested?
couldn't they have bested? 	couldn't I have been besting?
couldn't you have been besting?
couldn't she have been besting?
couldn't we have been besting?
couldn't you have been besting?
couldn't they have been besting?