English verb conjugation
COULD TUB

Regular verb: tub - tubbed - tubbed

Affirmation

Simple form	V-ing form
I could tub you could tub she could tub we could tub you could tub they could tub	I could be tubbing you could be tubbing she could be tubbing we could be tubbing you could be tubbing they could be tubbing
Perfect	V-ing perfect
I could have tubbed you could have tubbed she could have tubbed we could have tubbed you could have tubbed they could have tubbed	I could have been tubbing you could have been tubbing she could have been tubbing we could have been tubbing you could have been tubbing they could have been tubbing

Negation

Simple form	V-ing form
I couldn't tub you couldn't tub she couldn't tub we couldn't tub you couldn't tub they couldn't tub	I couldn't be tubbing you couldn't be tubbing she couldn't be tubbing we couldn't be tubbing you couldn't be tubbing they couldn't be tubbing
Perfect	V-ing perfect
I couldn't have tubbed you couldn't have tubbed she couldn't have tubbed we couldn't have tubbed you couldn't have tubbed they couldn't have tubbed	I couldn't have been tubbing you couldn't have been tubbing she couldn't have been tubbing we couldn't have been tubbing you couldn't have been tubbing they couldn't have been tubbing

Interrogative form

Simple form	V-ing form
could I tub? could you tub? could she tub? could we tub? could you tub? could they tub?	could I be tubbing? could you be tubbing? could she be tubbing? could we be tubbing? could you be tubbing? could they be tubbing?
Perfect	V-ing perfect
could I have tubbed? could you have tubbed? could she have tubbed? could we have tubbed? could you have tubbed? could they have tubbed?	could I have been tubbing? could you have been tubbing? could she have been tubbing? could we have been tubbing? could you have been tubbing? could they have been tubbing?

Interro-negative form

Simple form	V-ing form
couldn't I tub? couldn't you tub? couldn't she tub? couldn't we tub? couldn't you tub? couldn't they tub?	couldn't I be tubbing? couldn't you be tubbing? couldn't she be tubbing? couldn't we be tubbing? couldn't you be tubbing? couldn't they be tubbing?
Perfect	V-ing perfect
couldn't I have tubbed? couldn't you have tubbed? couldn't she have tubbed? couldn't we have tubbed? couldn't you have tubbed? couldn't they have tubbed?	couldn't I have been tubbing? couldn't you have been tubbing? couldn't she have been tubbing? couldn't we have been tubbing? couldn't you have been tubbing? couldn't they have been tubbing?