I can participate you can participate he can participate we can participate you can participate they can participate
V-ing form
I can be participating you can be participating he can be participating we can be participating you can be participating they can be participating
Perfect
I can have participated you can have participated he can have participated we can have participated you can have participated they can have participated
V-ing perfect
I can have been participating you can have been participating he can have been participating we can have been participating you can have been participating they can have been participating
Negation
Simple form
I can't participate you can't participate he can't participate we can't participate you can't participate they can't participate
V-ing form
I can't be participating you can't be participating he can't be participating we can't be participating you can't be participating they can't be participating
Perfect
I can't have participated you can't have participated he can't have participated we can't have participated you can't have participated they can't have participated
V-ing perfect
I can't have been participating you can't have been participating he can't have been participating we can't have been participating you can't have been participating they can't have been participating
Interrogative form
Simple form
can I participate? can you participate? can he participate? can we participate? can you participate? can they participate?
V-ing form
can I be participating? can you be participating? can he be participating? can we be participating? can you be participating? can they be participating?
Perfect
can I have participated? can you have participated? can he have participated? can we have participated? can you have participated? can they have participated?
V-ing perfect
can I have been participating? can you have been participating? can he have been participating? can we have been participating? can you have been participating? can they have been participating?
Interro-negative form
Simple form
can't I participate? can't you participate? can't he participate? can't we participate? can't you participate? can't they participate?
V-ing form
can't I be participating? can't you be participating? can't he be participating? can't we be participating? can't you be participating? can't they be participating?
Perfect
can't I have participated? can't you have participated? can't he have participated? can't we have participated? can't you have participated? can't they have participated?
V-ing perfect
can't I have been participating? can't you have been participating? can't he have been participating? can't we have been participating? can't you have been participating? can't they have been participating?