I could curd you could curd she could curd we could curd you could curd they could curd
V-ing form
I could be curding you could be curding she could be curding we could be curding you could be curding they could be curding
Perfect
I could have curded you could have curded she could have curded we could have curded you could have curded they could have curded
V-ing perfect
I could have been curding you could have been curding she could have been curding we could have been curding you could have been curding they could have been curding
Negation
Simple form
I couldn't curd you couldn't curd she couldn't curd we couldn't curd you couldn't curd they couldn't curd
V-ing form
I couldn't be curding you couldn't be curding she couldn't be curding we couldn't be curding you couldn't be curding they couldn't be curding
Perfect
I couldn't have curded you couldn't have curded she couldn't have curded we couldn't have curded you couldn't have curded they couldn't have curded
V-ing perfect
I couldn't have been curding you couldn't have been curding she couldn't have been curding we couldn't have been curding you couldn't have been curding they couldn't have been curding
Interrogative form
Simple form
could I curd? could you curd? could she curd? could we curd? could you curd? could they curd?
V-ing form
could I be curding? could you be curding? could she be curding? could we be curding? could you be curding? could they be curding?
Perfect
could I have curded? could you have curded? could she have curded? could we have curded? could you have curded? could they have curded?
V-ing perfect
could I have been curding? could you have been curding? could she have been curding? could we have been curding? could you have been curding? could they have been curding?
Interro-negative form
Simple form
couldn't I curd? couldn't you curd? couldn't she curd? couldn't we curd? couldn't you curd? couldn't they curd?
V-ing form
couldn't I be curding? couldn't you be curding? couldn't she be curding? couldn't we be curding? couldn't you be curding? couldn't they be curding?
Perfect
couldn't I have curded? couldn't you have curded? couldn't she have curded? couldn't we have curded? couldn't you have curded? couldn't they have curded?
V-ing perfect
couldn't I have been curding? couldn't you have been curding? couldn't she have been curding? couldn't we have been curding? couldn't you have been curding? couldn't they have been curding?