I can approach you can approach he can approach we can approach you can approach they can approach
V-ing form
I can be approaching you can be approaching he can be approaching we can be approaching you can be approaching they can be approaching
Perfect
I can have approached you can have approached he can have approached we can have approached you can have approached they can have approached
V-ing perfect
I can have been approaching you can have been approaching he can have been approaching we can have been approaching you can have been approaching they can have been approaching
Negation
Simple form
I can't approach you can't approach he can't approach we can't approach you can't approach they can't approach
V-ing form
I can't be approaching you can't be approaching he can't be approaching we can't be approaching you can't be approaching they can't be approaching
Perfect
I can't have approached you can't have approached he can't have approached we can't have approached you can't have approached they can't have approached
V-ing perfect
I can't have been approaching you can't have been approaching he can't have been approaching we can't have been approaching you can't have been approaching they can't have been approaching
Interrogative form
Simple form
can I approach? can you approach? can he approach? can we approach? can you approach? can they approach?
V-ing form
can I be approaching? can you be approaching? can he be approaching? can we be approaching? can you be approaching? can they be approaching?
Perfect
can I have approached? can you have approached? can he have approached? can we have approached? can you have approached? can they have approached?
V-ing perfect
can I have been approaching? can you have been approaching? can he have been approaching? can we have been approaching? can you have been approaching? can they have been approaching?
Interro-negative form
Simple form
can't I approach? can't you approach? can't he approach? can't we approach? can't you approach? can't they approach?
V-ing form
can't I be approaching? can't you be approaching? can't he be approaching? can't we be approaching? can't you be approaching? can't they be approaching?
Perfect
can't I have approached? can't you have approached? can't he have approached? can't we have approached? can't you have approached? can't they have approached?
V-ing perfect
can't I have been approaching? can't you have been approaching? can't he have been approaching? can't we have been approaching? can't you have been approaching? can't they have been approaching?