English verb conjugation
COULD STRAITEN

Regular verb: straiten - straitened - straitened

Affirmation

Simple form	V-ing form
I could straiten you could straiten he could straiten we could straiten you could straiten they could straiten	I could be straitening you could be straitening he could be straitening we could be straitening you could be straitening they could be straitening
Perfect	V-ing perfect
I could have straitened you could have straitened he could have straitened we could have straitened you could have straitened they could have straitened	I could have been straitening you could have been straitening he could have been straitening we could have been straitening you could have been straitening they could have been straitening

Negation

Simple form	V-ing form
I couldn't straiten you couldn't straiten he couldn't straiten we couldn't straiten you couldn't straiten they couldn't straiten	I couldn't be straitening you couldn't be straitening he couldn't be straitening we couldn't be straitening you couldn't be straitening they couldn't be straitening
Perfect	V-ing perfect
I couldn't have straitened you couldn't have straitened he couldn't have straitened we couldn't have straitened you couldn't have straitened they couldn't have straitened	I couldn't have been straitening you couldn't have been straitening he couldn't have been straitening we couldn't have been straitening you couldn't have been straitening they couldn't have been straitening

Interrogative form

Simple form	V-ing form
could I straiten? could you straiten? could he straiten? could we straiten? could you straiten? could they straiten?	could I be straitening? could you be straitening? could he be straitening? could we be straitening? could you be straitening? could they be straitening?
Perfect	V-ing perfect
could I have straitened? could you have straitened? could he have straitened? could we have straitened? could you have straitened? could they have straitened?	could I have been straitening? could you have been straitening? could he have been straitening? could we have been straitening? could you have been straitening? could they have been straitening?

Interro-negative form

Simple form	V-ing form
couldn't I straiten? couldn't you straiten? couldn't he straiten? couldn't we straiten? couldn't you straiten? couldn't they straiten?	couldn't I be straitening? couldn't you be straitening? couldn't he be straitening? couldn't we be straitening? couldn't you be straitening? couldn't they be straitening?
Perfect	V-ing perfect
couldn't I have straitened? couldn't you have straitened? couldn't he have straitened? couldn't we have straitened? couldn't you have straitened? couldn't they have straitened?	couldn't I have been straitening? couldn't you have been straitening? couldn't he have been straitening? couldn't we have been straitening? couldn't you have been straitening? couldn't they have been straitening?