Present perfect + when + (past simple / present perfect)?

Question

I have no idea what tense should I use after the "when clause" when the first part of a sentence is in present perfect. Should I use past simple (continuous) or present perfect (continuous)?

I've done this many times before when I was helping my uncle.

I've done this many times before when I've been helping my uncle.

 

I have done a lot of crazy things when I was with my friends.

I have done a lot of crazy things when I've been with my friends.

Which versions are correct?

Answer 1

The basic trouble with the "when" clauses here is that you have a present perfect, it is a present tense, and the "when" should be "now".

I have done a lot of crazy things when I (was/have been) with my friends.

This is borderline acceptable. It is slightly odd, because the when clause still jars with the present perfect. But it could be understood to describe the situation in which you did crazy things instead of the time. Even so, past tense would be better:

I did a lot of crazy things when I was with my friends.

The first examples could rendered with a past perfect:

I had already done it many times when I started helping my uncle.

Or split into two sentences, one in the present (perfect) and one in the past:

I have done this many times. I first did it before helping my uncle.

Remember, its a present perfect, so the time implied is "now".

Answer 2

Native speakers of English would use the word "while"

• I have done this many times before while I was helping my uncle.
• I have done a lot of crazy things while I was with my friends.

You are allowed to omit the phrase "I was:"

• I have done a lot of crazy things with my friends.
• I have done this many times before while helping my uncle.