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