English verb conjugation
COULD TOMB

Regular verb: tomb - tombed - tombed

Affirmation

Simple form	V-ing form
I could tomb you could tomb he could tomb we could tomb you could tomb they could tomb	I could be tombing you could be tombing he could be tombing we could be tombing you could be tombing they could be tombing
Perfect	V-ing perfect
I could have tombed you could have tombed he could have tombed we could have tombed you could have tombed they could have tombed	I could have been tombing you could have been tombing he could have been tombing we could have been tombing you could have been tombing they could have been tombing

Negation

Simple form	V-ing form
I couldn't tomb you couldn't tomb he couldn't tomb we couldn't tomb you couldn't tomb they couldn't tomb	I couldn't be tombing you couldn't be tombing he couldn't be tombing we couldn't be tombing you couldn't be tombing they couldn't be tombing
Perfect	V-ing perfect
I couldn't have tombed you couldn't have tombed he couldn't have tombed we couldn't have tombed you couldn't have tombed they couldn't have tombed	I couldn't have been tombing you couldn't have been tombing he couldn't have been tombing we couldn't have been tombing you couldn't have been tombing they couldn't have been tombing

Interrogative form

Simple form	V-ing form
could I tomb? could you tomb? could he tomb? could we tomb? could you tomb? could they tomb?	could I be tombing? could you be tombing? could he be tombing? could we be tombing? could you be tombing? could they be tombing?
Perfect	V-ing perfect
could I have tombed? could you have tombed? could he have tombed? could we have tombed? could you have tombed? could they have tombed?	could I have been tombing? could you have been tombing? could he have been tombing? could we have been tombing? could you have been tombing? could they have been tombing?

Interro-negative form

Simple form	V-ing form
couldn't I tomb? couldn't you tomb? couldn't he tomb? couldn't we tomb? couldn't you tomb? couldn't they tomb?	couldn't I be tombing? couldn't you be tombing? couldn't he be tombing? couldn't we be tombing? couldn't you be tombing? couldn't they be tombing?
Perfect	V-ing perfect
couldn't I have tombed? couldn't you have tombed? couldn't he have tombed? couldn't we have tombed? couldn't you have tombed? couldn't they have tombed?	couldn't I have been tombing? couldn't you have been tombing? couldn't he have been tombing? couldn't we have been tombing? couldn't you have been tombing? couldn't they have been tombing?