English verb conjugation
CAN ENTER

Regular verb: enter - entered - entered

Affirmation

Simple form	V-ing form
I can enter you can enter he can enter we can enter you can enter they can enter	I can be entering you can be entering he can be entering we can be entering you can be entering they can be entering
Perfect	V-ing perfect
I can have entered you can have entered he can have entered we can have entered you can have entered they can have entered	I can have been entering you can have been entering he can have been entering we can have been entering you can have been entering they can have been entering

Negation

Simple form	V-ing form
I can't enter you can't enter he can't enter we can't enter you can't enter they can't enter	I can't be entering you can't be entering he can't be entering we can't be entering you can't be entering they can't be entering
Perfect	V-ing perfect
I can't have entered you can't have entered he can't have entered we can't have entered you can't have entered they can't have entered	I can't have been entering you can't have been entering he can't have been entering we can't have been entering you can't have been entering they can't have been entering

Interrogative form

Simple form	V-ing form
can I enter? can you enter? can he enter? can we enter? can you enter? can they enter?	can I be entering? can you be entering? can he be entering? can we be entering? can you be entering? can they be entering?
Perfect	V-ing perfect
can I have entered? can you have entered? can he have entered? can we have entered? can you have entered? can they have entered?	can I have been entering? can you have been entering? can he have been entering? can we have been entering? can you have been entering? can they have been entering?

Interro-negative form

Simple form	V-ing form
can't I enter? can't you enter? can't he enter? can't we enter? can't you enter? can't they enter?	can't I be entering? can't you be entering? can't he be entering? can't we be entering? can't you be entering? can't they be entering?
Perfect	V-ing perfect
can't I have entered? can't you have entered? can't he have entered? can't we have entered? can't you have entered? can't they have entered?	can't I have been entering? can't you have been entering? can't he have been entering? can't we have been entering? can't you have been entering? can't they have been entering?