I visit my friends - Present Simple
I visiting my friends - Present Continuous
I have been visiting my friends - Present Perfect Continuous
I have visited my friends - Present Perfect
I visited my friends - Past Simple
I was visiting my friends - Past Continuous
I had been visiting my friends - PastPerfect Continuous
I had visited my friends - PastPerfect
I will visit my friends - Future Simple
I will be visiting my friends - Future Continuous
I will have been visiting my friends- Future Perfect Continuous
I will have visited my friends - Future Perfect