Regular verb: happen - happened - happened
Simple form | V-ing form |
- - it would happen - - - | - - it would be happening - - - |
Perfect | V-ing perfect |
- - it would have happened - - - | - - it would have been happening - - - |
Simple form | V-ing form |
- - it would not happen - - - | - - it would not be happening - - - |
Perfect | V-ing perfect |
- - it would not have happened - - - | - - it would not have been happening - - - |
Simple form | V-ing form |
- - would it happen? - - - | - - would it be happening? - - - |
Perfect | V-ing perfect |
- - would it have happened? - - - | - - would it have been happening? - - - |
Simple form | V-ing form |
- - would it not happen? - - - | - - would it not be happening? - - - |
Perfect | V-ing perfect |
- - would it not have happened? - - - | - - would it not have been happening? - - - |