I'm having trouble with how I say I finished doing something, as opposed to: I used to do something, and the have/had done something (in Mandarin Chinese.) I know that the markers 'guo' and 'le' both connotate something done in the past; however there are circumstances where I see one used or another, and it's not clear; moreover sometimes they are both used and I don't know what to infer from that.
So for example, how would I say
1. 'I studied this afternoon' - something very recent that I just finished doing; and
2. 'I used to climb trees when I was younger' - the typical imperfect past;
3. 'I have read that book' or 'I have been to Japan' something along the lines of, I've done that before and it's a finished task that's 'perfectly' finished?
Thanks guys - I've noticed it's very interesting, when learning new languages, especially to see how the past tense is dealt with in many different ways.