Verbo regolare: happen - happened - happened
Forma semplice | Forma con V-ing |
- - it can happen - - - | - - it can be happening - - - |
Perfetto | Perfetto con V-ing |
- - it can have happened - - - | - - it can have been happening - - - |
Forma semplice | Forma con V-ing |
- - it cannot happen - - - | - - it cannot be happening - - - |
Perfetto | Perfetto con V-ing |
- - it cannot have happened - - - | - - it cannot have been happening - - - |
Forma semplice | Forma con V-ing |
- - can it happen? - - - | - - can it be happening? - - - |
Perfetto | Perfetto con V-ing |
- - can it have happened? - - - | - - can it have been happening? - - - |
Forma semplice | Forma con V-ing |
- - can it not happen? - - - | - - can it not be happening? - - - |
Perfetto | Perfetto con V-ing |
- - can it not have happened? - - - | - - can it not have been happening? - - - |