I could excite you could excite he could excite we could excite you could excite they could excite
V-ing form
I could be exciting you could be exciting he could be exciting we could be exciting you could be exciting they could be exciting
Perfect
I could have excited you could have excited he could have excited we could have excited you could have excited they could have excited
V-ing perfect
I could have been exciting you could have been exciting he could have been exciting we could have been exciting you could have been exciting they could have been exciting
Negation
Simple form
I couldn't excite you couldn't excite he couldn't excite we couldn't excite you couldn't excite they couldn't excite
V-ing form
I couldn't be exciting you couldn't be exciting he couldn't be exciting we couldn't be exciting you couldn't be exciting they couldn't be exciting
Perfect
I couldn't have excited you couldn't have excited he couldn't have excited we couldn't have excited you couldn't have excited they couldn't have excited
V-ing perfect
I couldn't have been exciting you couldn't have been exciting he couldn't have been exciting we couldn't have been exciting you couldn't have been exciting they couldn't have been exciting
Interrogative form
Simple form
could I excite? could you excite? could he excite? could we excite? could you excite? could they excite?
V-ing form
could I be exciting? could you be exciting? could he be exciting? could we be exciting? could you be exciting? could they be exciting?
Perfect
could I have excited? could you have excited? could he have excited? could we have excited? could you have excited? could they have excited?
V-ing perfect
could I have been exciting? could you have been exciting? could he have been exciting? could we have been exciting? could you have been exciting? could they have been exciting?
Interro-negative form
Simple form
couldn't I excite? couldn't you excite? couldn't he excite? couldn't we excite? couldn't you excite? couldn't they excite?
V-ing form
couldn't I be exciting? couldn't you be exciting? couldn't he be exciting? couldn't we be exciting? couldn't you be exciting? couldn't they be exciting?
Perfect
couldn't I have excited? couldn't you have excited? couldn't he have excited? couldn't we have excited? couldn't you have excited? couldn't they have excited?
V-ing perfect
couldn't I have been exciting? couldn't you have been exciting? couldn't he have been exciting? couldn't we have been exciting? couldn't you have been exciting? couldn't they have been exciting?