English verb conjugation
COULD SIGNIFY

Regular verb: signify - signified - signified

Affirmation

Simple form	V-ing form
I could signify you could signify she could signify we could signify you could signify they could signify	I could be signifying you could be signifying she could be signifying we could be signifying you could be signifying they could be signifying
Perfect	V-ing perfect
I could have signified you could have signified she could have signified we could have signified you could have signified they could have signified	I could have been signifying you could have been signifying she could have been signifying we could have been signifying you could have been signifying they could have been signifying

Negation

Simple form	V-ing form
I couldn't signify you couldn't signify she couldn't signify we couldn't signify you couldn't signify they couldn't signify	I couldn't be signifying you couldn't be signifying she couldn't be signifying we couldn't be signifying you couldn't be signifying they couldn't be signifying
Perfect	V-ing perfect
I couldn't have signified you couldn't have signified she couldn't have signified we couldn't have signified you couldn't have signified they couldn't have signified	I couldn't have been signifying you couldn't have been signifying she couldn't have been signifying we couldn't have been signifying you couldn't have been signifying they couldn't have been signifying

Interrogative form

Simple form	V-ing form
could I signify? could you signify? could she signify? could we signify? could you signify? could they signify?	could I be signifying? could you be signifying? could she be signifying? could we be signifying? could you be signifying? could they be signifying?
Perfect	V-ing perfect
could I have signified? could you have signified? could she have signified? could we have signified? could you have signified? could they have signified?	could I have been signifying? could you have been signifying? could she have been signifying? could we have been signifying? could you have been signifying? could they have been signifying?

Interro-negative form

Simple form	V-ing form
couldn't I signify? couldn't you signify? couldn't she signify? couldn't we signify? couldn't you signify? couldn't they signify?	couldn't I be signifying? couldn't you be signifying? couldn't she be signifying? couldn't we be signifying? couldn't you be signifying? couldn't they be signifying?
Perfect	V-ing perfect
couldn't I have signified? couldn't you have signified? couldn't she have signified? couldn't we have signified? couldn't you have signified? couldn't they have signified?	couldn't I have been signifying? couldn't you have been signifying? couldn't she have been signifying? couldn't we have been signifying? couldn't you have been signifying? couldn't they have been signifying?