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