Present perfect (since, for, yet, just, never, ever) Present perfect (since, for, yet, just, never, ever)
U2 song: I still haven't found what I'm looking for. U2 song: I still haven't found what I'm looking for.
Simple past and present perfect: questions and answers Simple past and present perfect: questions and answers
Present perfect with just, yet, before, never, ever Present perfect with just, yet, before, never, ever