Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I could re-tighten you could re-tighten she could re-tighten we could re-tighten you could re-tighten they could re-tighten
V-ing form
I could be re-tightening you could be re-tightening she could be re-tightening we could be re-tightening you could be re-tightening they could be re-tightening
Perfect
I could have re-tightened you could have re-tightened she could have re-tightened we could have re-tightened you could have re-tightened they could have re-tightened
V-ing perfect
I could have been re-tightening you could have been re-tightening she could have been re-tightening we could have been re-tightening you could have been re-tightening they could have been re-tightening
Negation
Simple form
I couldn't re-tighten you couldn't re-tighten she couldn't re-tighten we couldn't re-tighten you couldn't re-tighten they couldn't re-tighten
V-ing form
I couldn't be re-tightening you couldn't be re-tightening she couldn't be re-tightening we couldn't be re-tightening you couldn't be re-tightening they couldn't be re-tightening
Perfect
I couldn't have re-tightened you couldn't have re-tightened she couldn't have re-tightened we couldn't have re-tightened you couldn't have re-tightened they couldn't have re-tightened
V-ing perfect
I couldn't have been re-tightening you couldn't have been re-tightening she couldn't have been re-tightening we couldn't have been re-tightening you couldn't have been re-tightening they couldn't have been re-tightening
Interrogative form
Simple form
could I re-tighten? could you re-tighten? could she re-tighten? could we re-tighten? could you re-tighten? could they re-tighten?
V-ing form
could I be re-tightening? could you be re-tightening? could she be re-tightening? could we be re-tightening? could you be re-tightening? could they be re-tightening?
Perfect
could I have re-tightened? could you have re-tightened? could she have re-tightened? could we have re-tightened? could you have re-tightened? could they have re-tightened?
V-ing perfect
could I have been re-tightening? could you have been re-tightening? could she have been re-tightening? could we have been re-tightening? could you have been re-tightening? could they have been re-tightening?
Interro-negative form
Simple form
couldn't I re-tighten? couldn't you re-tighten? couldn't she re-tighten? couldn't we re-tighten? couldn't you re-tighten? couldn't they re-tighten?
V-ing form
couldn't I be re-tightening? couldn't you be re-tightening? couldn't she be re-tightening? couldn't we be re-tightening? couldn't you be re-tightening? couldn't they be re-tightening?
Perfect
couldn't I have re-tightened? couldn't you have re-tightened? couldn't she have re-tightened? couldn't we have re-tightened? couldn't you have re-tightened? couldn't they have re-tightened?
V-ing perfect
couldn't I have been re-tightening? couldn't you have been re-tightening? couldn't she have been re-tightening? couldn't we have been re-tightening? couldn't you have been re-tightening? couldn't they have been re-tightening?