English verb conjugation
CAN COUNTERCHECK

Regular verb: countercheck - counterchecked - counterchecked

Affirmation

Simple form	V-ing form
I can countercheck you can countercheck he can countercheck we can countercheck you can countercheck they can countercheck	I can be counterchecking you can be counterchecking he can be counterchecking we can be counterchecking you can be counterchecking they can be counterchecking
Perfect	V-ing perfect
I can have counterchecked you can have counterchecked he can have counterchecked we can have counterchecked you can have counterchecked they can have counterchecked	I can have been counterchecking you can have been counterchecking he can have been counterchecking we can have been counterchecking you can have been counterchecking they can have been counterchecking

Negation

Simple form	V-ing form
I cannot countercheck you cannot countercheck he cannot countercheck we cannot countercheck you cannot countercheck they cannot countercheck	I cannot be counterchecking you cannot be counterchecking he cannot be counterchecking we cannot be counterchecking you cannot be counterchecking they cannot be counterchecking
Perfect	V-ing perfect
I cannot have counterchecked you cannot have counterchecked he cannot have counterchecked we cannot have counterchecked you cannot have counterchecked they cannot have counterchecked	I cannot have been counterchecking you cannot have been counterchecking he cannot have been counterchecking we cannot have been counterchecking you cannot have been counterchecking they cannot have been counterchecking

Interrogative form

Simple form	V-ing form
can I countercheck? can you countercheck? can he countercheck? can we countercheck? can you countercheck? can they countercheck?	can I be counterchecking? can you be counterchecking? can he be counterchecking? can we be counterchecking? can you be counterchecking? can they be counterchecking?
Perfect	V-ing perfect
can I have counterchecked? can you have counterchecked? can he have counterchecked? can we have counterchecked? can you have counterchecked? can they have counterchecked?	can I have been counterchecking? can you have been counterchecking? can he have been counterchecking? can we have been counterchecking? can you have been counterchecking? can they have been counterchecking?

Interro-negative form

Simple form	V-ing form
can I not countercheck? can you not countercheck? can he not countercheck? can we not countercheck? can you not countercheck? can they not countercheck?	can I not be counterchecking? can you not be counterchecking? can he not be counterchecking? can we not be counterchecking? can you not be counterchecking? can they not be counterchecking?
Perfect	V-ing perfect
can I not have counterchecked? can you not have counterchecked? can he not have counterchecked? can we not have counterchecked? can you not have counterchecked? can they not have counterchecked?	can I not have been counterchecking? can you not have been counterchecking? can he not have been counterchecking? can we not have been counterchecking? can you not have been counterchecking? can they not have been counterchecking?