English verb conjugation
COULD CREDIT

Regular verb: credit - credited - credited

Affirmation

Simple form	V-ing form
I could credit you could credit he could credit we could credit you could credit they could credit	I could be crediting you could be crediting he could be crediting we could be crediting you could be crediting they could be crediting
Perfect	V-ing perfect
I could have credited you could have credited he could have credited we could have credited you could have credited they could have credited	I could have been crediting you could have been crediting he could have been crediting we could have been crediting you could have been crediting they could have been crediting

Negation

Simple form	V-ing form
I couldn't credit you couldn't credit he couldn't credit we couldn't credit you couldn't credit they couldn't credit	I couldn't be crediting you couldn't be crediting he couldn't be crediting we couldn't be crediting you couldn't be crediting they couldn't be crediting
Perfect	V-ing perfect
I couldn't have credited you couldn't have credited he couldn't have credited we couldn't have credited you couldn't have credited they couldn't have credited	I couldn't have been crediting you couldn't have been crediting he couldn't have been crediting we couldn't have been crediting you couldn't have been crediting they couldn't have been crediting

Interrogative form

Simple form	V-ing form
could I credit? could you credit? could he credit? could we credit? could you credit? could they credit?	could I be crediting? could you be crediting? could he be crediting? could we be crediting? could you be crediting? could they be crediting?
Perfect	V-ing perfect
could I have credited? could you have credited? could he have credited? could we have credited? could you have credited? could they have credited?	could I have been crediting? could you have been crediting? could he have been crediting? could we have been crediting? could you have been crediting? could they have been crediting?

Interro-negative form

Simple form	V-ing form
couldn't I credit? couldn't you credit? couldn't he credit? couldn't we credit? couldn't you credit? couldn't they credit?	couldn't I be crediting? couldn't you be crediting? couldn't he be crediting? couldn't we be crediting? couldn't you be crediting? couldn't they be crediting?
Perfect	V-ing perfect
couldn't I have credited? couldn't you have credited? couldn't he have credited? couldn't we have credited? couldn't you have credited? couldn't they have credited?	couldn't I have been crediting? couldn't you have been crediting? couldn't he have been crediting? couldn't we have been crediting? couldn't you have been crediting? couldn't they have been crediting?