Regular verb: improve - improved - improved
Simple form | V-ing form |
I could improve you could improve she could improve we could improve you could improve they could improve | I could be improving you could be improving she could be improving we could be improving you could be improving they could be improving |
Perfect | V-ing perfect |
I could have improved you could have improved she could have improved we could have improved you could have improved they could have improved | I could have been improving you could have been improving she could have been improving we could have been improving you could have been improving they could have been improving |
Simple form | V-ing form |
I couldn't improve you couldn't improve she couldn't improve we couldn't improve you couldn't improve they couldn't improve | I couldn't be improving you couldn't be improving she couldn't be improving we couldn't be improving you couldn't be improving they couldn't be improving |
Perfect | V-ing perfect |
I couldn't have improved you couldn't have improved she couldn't have improved we couldn't have improved you couldn't have improved they couldn't have improved | I couldn't have been improving you couldn't have been improving she couldn't have been improving we couldn't have been improving you couldn't have been improving they couldn't have been improving |
Simple form | V-ing form |
could I improve? could you improve? could she improve? could we improve? could you improve? could they improve? | could I be improving? could you be improving? could she be improving? could we be improving? could you be improving? could they be improving? |
Perfect | V-ing perfect |
could I have improved? could you have improved? could she have improved? could we have improved? could you have improved? could they have improved? | could I have been improving? could you have been improving? could she have been improving? could we have been improving? could you have been improving? could they have been improving? |
Simple form | V-ing form |
couldn't I improve? couldn't you improve? couldn't she improve? couldn't we improve? couldn't you improve? couldn't they improve? | couldn't I be improving? couldn't you be improving? couldn't she be improving? couldn't we be improving? couldn't you be improving? couldn't they be improving? |
Perfect | V-ing perfect |
couldn't I have improved? couldn't you have improved? couldn't she have improved? couldn't we have improved? couldn't you have improved? couldn't they have improved? | couldn't I have been improving? couldn't you have been improving? couldn't she have been improving? couldn't we have been improving? couldn't you have been improving? couldn't they have been improving? |