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