English verb conjugation
COULD SOB

Regular verb: sob - sobbed - sobbed

Affirmation

Simple form	V-ing form
I could sob you could sob he could sob we could sob you could sob they could sob	I could be sobbing you could be sobbing he could be sobbing we could be sobbing you could be sobbing they could be sobbing
Perfect	V-ing perfect
I could have sobbed you could have sobbed he could have sobbed we could have sobbed you could have sobbed they could have sobbed	I could have been sobbing you could have been sobbing he could have been sobbing we could have been sobbing you could have been sobbing they could have been sobbing

Negation

Simple form	V-ing form
I couldn't sob you couldn't sob he couldn't sob we couldn't sob you couldn't sob they couldn't sob	I couldn't be sobbing you couldn't be sobbing he couldn't be sobbing we couldn't be sobbing you couldn't be sobbing they couldn't be sobbing
Perfect	V-ing perfect
I couldn't have sobbed you couldn't have sobbed he couldn't have sobbed we couldn't have sobbed you couldn't have sobbed they couldn't have sobbed	I couldn't have been sobbing you couldn't have been sobbing he couldn't have been sobbing we couldn't have been sobbing you couldn't have been sobbing they couldn't have been sobbing

Interrogative form

Simple form	V-ing form
could I sob? could you sob? could he sob? could we sob? could you sob? could they sob?	could I be sobbing? could you be sobbing? could he be sobbing? could we be sobbing? could you be sobbing? could they be sobbing?
Perfect	V-ing perfect
could I have sobbed? could you have sobbed? could he have sobbed? could we have sobbed? could you have sobbed? could they have sobbed?	could I have been sobbing? could you have been sobbing? could he have been sobbing? could we have been sobbing? could you have been sobbing? could they have been sobbing?

Interro-negative form

Simple form	V-ing form
couldn't I sob? couldn't you sob? couldn't he sob? couldn't we sob? couldn't you sob? couldn't they sob?	couldn't I be sobbing? couldn't you be sobbing? couldn't he be sobbing? couldn't we be sobbing? couldn't you be sobbing? couldn't they be sobbing?
Perfect	V-ing perfect
couldn't I have sobbed? couldn't you have sobbed? couldn't he have sobbed? couldn't we have sobbed? couldn't you have sobbed? couldn't they have sobbed?	couldn't I have been sobbing? couldn't you have been sobbing? couldn't he have been sobbing? couldn't we have been sobbing? couldn't you have been sobbing? couldn't they have been sobbing?