I could unload you could unload he could unload we could unload you could unload they could unload
V-ing form
I could be unloading you could be unloading he could be unloading we could be unloading you could be unloading they could be unloading
Perfect
I could have unloaded you could have unloaded he could have unloaded we could have unloaded you could have unloaded they could have unloaded
V-ing perfect
I could have been unloading you could have been unloading he could have been unloading we could have been unloading you could have been unloading they could have been unloading
Negation
Simple form
I could not unload you could not unload he could not unload we could not unload you could not unload they could not unload
V-ing form
I could not be unloading you could not be unloading he could not be unloading we could not be unloading you could not be unloading they could not be unloading
Perfect
I could not have unloaded you could not have unloaded he could not have unloaded we could not have unloaded you could not have unloaded they could not have unloaded
V-ing perfect
I could not have been unloading you could not have been unloading he could not have been unloading we could not have been unloading you could not have been unloading they could not have been unloading
Interrogative form
Simple form
could I unload? could you unload? could he unload? could we unload? could you unload? could they unload?
V-ing form
could I be unloading? could you be unloading? could he be unloading? could we be unloading? could you be unloading? could they be unloading?
Perfect
could I have unloaded? could you have unloaded? could he have unloaded? could we have unloaded? could you have unloaded? could they have unloaded?
V-ing perfect
could I have been unloading? could you have been unloading? could he have been unloading? could we have been unloading? could you have been unloading? could they have been unloading?
Interro-negative form
Simple form
could I not unload? could you not unload? could he not unload? could we not unload? could you not unload? could they not unload?
V-ing form
could I not be unloading? could you not be unloading? could he not be unloading? could we not be unloading? could you not be unloading? could they not be unloading?
Perfect
could I not have unloaded? could you not have unloaded? could he not have unloaded? could we not have unloaded? could you not have unloaded? could they not have unloaded?
V-ing perfect
could I not have been unloading? could you not have been unloading? could he not have been unloading? could we not have been unloading? could you not have been unloading? could they not have been unloading?