could tweak
Regular verb: tweak - tweaked- tweaked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could tweak
you could tweak
she could tweak
we could tweak
you could tweak
they could tweak 	I could be tweaking
you could be tweaking
she could be tweaking
we could be tweaking
you could be tweaking
they could be tweaking	I could have tweaked
you could have tweaked
she could have tweaked
we could have tweaked
you could have tweaked
they could have tweaked	I could have been tweaking
you could have been tweaking
she could have been tweaking
we could have been tweaking
you could have been tweaking
they could have been tweaking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not tweak
you could not tweak
she could not tweak
we could not tweak
you could not tweak
they could not tweak 	I could not be tweaking
you could not be tweaking
she could not be tweaking
we could not be tweaking
you could not be tweaking
they could not be tweaking	I could not have tweaked
you could not have tweaked
she could not have tweaked
we could not have tweaked
you could not have tweaked
they could not have tweaked	I could not have been tweaking
you could not have been tweaking
she could not have been tweaking
we could not have been tweaking
you could not have been tweaking
they could not have been tweaking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I tweak?
could you tweak?
could she tweak?
could we tweak?
could you tweak?
could they tweak? 	could I be tweaking?
could you be tweaking?
could she be tweaking?
could we be tweaking?
could you be tweaking?
could they be tweaking? 	could I have tweaked?
could you have tweaked?
could she have tweaked?
could we have tweaked?
could you have tweaked?
could they have tweaked? 	could I have been tweaking?
could you have been tweaking?
could she have been tweaking?
could we have been tweaking?
could you have been tweaking?
could they have been tweaking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not tweak?
could you not tweak?
could she not tweak?
could we not tweak?
could you not tweak?
could they not tweak? 	could I not be tweaking?
could you not be tweaking?
could she not be tweaking?
could we not be tweaking?
could you not be tweaking?
could they not be tweaking? 	could I not have tweaked?
could you not have tweaked?
could she not have tweaked?
could we not have tweaked?
could you not have tweaked?
could they not have tweaked? 	could I not have been tweaking?
could you not have been tweaking?
could she not have been tweaking?
could we not have been tweaking?
could you not have been tweaking?
could they not have been tweaking?