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 cannot approach you cannot approach he cannot approach we cannot approach you cannot approach they cannot approach
V-ing form
I cannot be approaching you cannot be approaching he cannot be approaching we cannot be approaching you cannot be approaching they cannot be approaching
Perfect
I cannot have approached you cannot have approached he cannot have approached we cannot have approached you cannot have approached they cannot have approached
V-ing perfect
I cannot have been approaching you cannot have been approaching he cannot have been approaching we cannot have been approaching you cannot have been approaching they cannot 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 I not approach? can you not approach? can he not approach? can we not approach? can you not approach? can they not approach?
V-ing form
can I not be approaching? can you not be approaching? can he not be approaching? can we not be approaching? can you not be approaching? can they not be approaching?
Perfect
can I not have approached? can you not have approached? can he not have approached? can we not have approached? can you not have approached? can they not have approached?
V-ing perfect
can I not have been approaching? can you not have been approaching? can he not have been approaching? can we not have been approaching? can you not have been approaching? can they not have been approaching?