English verb conjugation
COULD ULULATE

Regular verb: ululate - ululated - ululated

Affirmation

Simple form	V-ing form
I could ululate you could ululate she could ululate we could ululate you could ululate they could ululate	I could be ululating you could be ululating she could be ululating we could be ululating you could be ululating they could be ululating
Perfect	V-ing perfect
I could have ululated you could have ululated she could have ululated we could have ululated you could have ululated they could have ululated	I could have been ululating you could have been ululating she could have been ululating we could have been ululating you could have been ululating they could have been ululating

Negation

Simple form	V-ing form
I couldn't ululate you couldn't ululate she couldn't ululate we couldn't ululate you couldn't ululate they couldn't ululate	I couldn't be ululating you couldn't be ululating she couldn't be ululating we couldn't be ululating you couldn't be ululating they couldn't be ululating
Perfect	V-ing perfect
I couldn't have ululated you couldn't have ululated she couldn't have ululated we couldn't have ululated you couldn't have ululated they couldn't have ululated	I couldn't have been ululating you couldn't have been ululating she couldn't have been ululating we couldn't have been ululating you couldn't have been ululating they couldn't have been ululating

Interrogative form

Simple form	V-ing form
could I ululate? could you ululate? could she ululate? could we ululate? could you ululate? could they ululate?	could I be ululating? could you be ululating? could she be ululating? could we be ululating? could you be ululating? could they be ululating?
Perfect	V-ing perfect
could I have ululated? could you have ululated? could she have ululated? could we have ululated? could you have ululated? could they have ululated?	could I have been ululating? could you have been ululating? could she have been ululating? could we have been ululating? could you have been ululating? could they have been ululating?

Interro-negative form

Simple form	V-ing form
couldn't I ululate? couldn't you ululate? couldn't she ululate? couldn't we ululate? couldn't you ululate? couldn't they ululate?	couldn't I be ululating? couldn't you be ululating? couldn't she be ululating? couldn't we be ululating? couldn't you be ululating? couldn't they be ululating?
Perfect	V-ing perfect
couldn't I have ululated? couldn't you have ululated? couldn't she have ululated? couldn't we have ululated? couldn't you have ululated? couldn't they have ululated?	couldn't I have been ululating? couldn't you have been ululating? couldn't she have been ululating? couldn't we have been ululating? couldn't you have been ululating? couldn't they have been ululating?