could yeast
Regular verb: yeast - yeasted- yeasted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could yeast
you could yeast
he could yeast
we could yeast
you could yeast
they could yeast 	I could be yeasting
you could be yeasting
he could be yeasting
we could be yeasting
you could be yeasting
they could be yeasting	I could have yeasted
you could have yeasted
he could have yeasted
we could have yeasted
you could have yeasted
they could have yeasted	I could have been yeasting
you could have been yeasting
he could have been yeasting
we could have been yeasting
you could have been yeasting
they could have been yeasting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't yeast
you couldn't yeast
he couldn't yeast
we couldn't yeast
you couldn't yeast
they couldn't yeast 	I couldn't be yeasting
you couldn't be yeasting
he couldn't be yeasting
we couldn't be yeasting
you couldn't be yeasting
they couldn't be yeasting	I couldn't have yeasted
you couldn't have yeasted
he couldn't have yeasted
we couldn't have yeasted
you couldn't have yeasted
they couldn't have yeasted	I couldn't have been yeasting
you couldn't have been yeasting
he couldn't have been yeasting
we couldn't have been yeasting
you couldn't have been yeasting
they couldn't have been yeasting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I yeast?
could you yeast?
could he yeast?
could we yeast?
could you yeast?
could they yeast? 	could I be yeasting?
could you be yeasting?
could he be yeasting?
could we be yeasting?
could you be yeasting?
could they be yeasting? 	could I have yeasted?
could you have yeasted?
could he have yeasted?
could we have yeasted?
could you have yeasted?
could they have yeasted? 	could I have been yeasting?
could you have been yeasting?
could he have been yeasting?
could we have been yeasting?
could you have been yeasting?
could they have been yeasting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I yeast?
couldn't you yeast?
couldn't he yeast?
couldn't we yeast?
couldn't you yeast?
couldn't they yeast? 	couldn't I be yeasting?
couldn't you be yeasting?
couldn't he be yeasting?
couldn't we be yeasting?
couldn't you be yeasting?
couldn't they be yeasting? 	couldn't I have yeasted?
couldn't you have yeasted?
couldn't he have yeasted?
couldn't we have yeasted?
couldn't you have yeasted?
couldn't they have yeasted? 	couldn't I have been yeasting?
couldn't you have been yeasting?
couldn't he have been yeasting?
couldn't we have been yeasting?
couldn't you have been yeasting?
couldn't they have been yeasting?