Present
I challenge
you challenge
he challenges
we challenge
you challenge
they challenge

Perfect
I have challenged
you have challenged
he has challenged
we have challenged
you have challenged
they have challenged

Past
I challenged
you challenged
he challenged
we challenged
you challenged
they challenged

Pluperfect
I had challenged
you had challenged
he had challenged
we had challenged
you had challenged
they had challenged

Future
I will challenge
you will challenge
he will challenge
we will challenge
you will challenge
they will challenge

Future perfect
I will have challenged
you will have challenged
he will have challenged
we will have challenged
you will have challenged
they will have challenged

Present
I challenge
you challenge
he challenge
we challenge
you challenge
they challenge

Present
I have challenged
you have challenged
he have challenged
we have challenged
you have challenged
they have challenged

Imperfect
I challenged
you challenged
he challenged
we challenged
you challenged
they challenged

Pluperfect
I had challenged
you had challenged
he had challenged
we had challenged
you had challenged
they had challenged

Present
I would challenge
you would challenge
he would challenge
we would challenge
you would challenge
they would challenge

Perfect
I would have challenged
you would have challenged
he would have challenged
we would have challenged
you would have challenged
they would have challenged

you challenge
we Let's challenge
you challenge

Present
I am challenging
you are challenging
he is challenging
we are challenging
you are challenging
they are challenging

Perfect
I have been challenging
you have been challenging
he has been challenging
we have been challenging
you have been challenging
they have been challenging

Past
I was challenging
you were challenging
he was challenging
we were challenging
you were challenging
they were challenging

Pluperfect
I had been challenging
you had been challenging
he had been challenging
we had been challenging
you had been challenging
they had been challenging

Future
I will be challenging
you will be challenging
he will be challenging
we will be challenging
you will be challenging
they will be challenging

Future perfect
I will have been challenging
you will have been challenging
he will have been challenging
we will have been challenging
you will have been challenging
they will have been challenging

Present
I would be challenging
you would be challenging
he would be challenging
we would be challenging
you would be challenging
they would be challenging

Perfect
I would have been challenging
you would have been challenging
he would have been challenging
we would have been challenging
you would have been challenging
they would have been challenging