How would I translate sentences like this:
1)Sen oynamışsın.
2)Ben beklemişim. 
3)O gelmiş.
etc...  

Quoting nemanjasrbHow would I translate sentences like this:1)Sen oynamışsın.2)Ben beklemişim. 3)O gelmiş.etc...  

my try

YOU HAVE PLAYED/ DANCED

I have waited

It /he/ she has come

I understand the meaning of those verbs,but how would I translate that sentences with MİŞ in general...  

I have the same wonder, does "miş" resemble the past perfect or what?

Some thoughts from learner, who as usual is not sure if what he´s talking is true but maybe you´ll still find it useful

One use of -mış which I´ve heard of is that it is used for inferential past tense - when you´re talking about situations about which you´ve heard that occured, or which apparently occured, but which have not been witnessed by you directly.

An example from Lewis´ "Turkish Grammar":

A: Geçmiş olsun, evinize hırsız girmiş.

B: Girdi, dedim.

Which means:

A: I hope you soon get over it; I hear your house has been burgled (speaker did not witness it, they have only heard about it).

B: Indeed (lit.: in fact, burglars entered it), I said. (speaker confirms that it indeed happened).

This made me think... because, we can´t be sure that speaker B have witnessed it as well. So maybe -mış tense is used when we want to indicate that we´re not sure about it, while -di tense is used when we want to stress that we´re certain that something had happened?

In finite verbs -mIş- denotes PAST + HEARSAY as tomac explained, in participles only PAST. Lewis´s example:

                      Plan hazırlanmış. ´I gather that the plan has been prepared.

                      hazırlanmış plan ´the plan which has been prepared´.

For another explanation click here

Post 5 gives a detailed explanation of when the miş tense is used.

In translating, often you can add the word apparently before the rest of the translation, eg 

1)Sen oynamışsın. Apparently you played (but I didn´t see you play)
2)Ben beklemişim. Apparently I waited (but I had forgotten that I waited)

3)O gelmiş. Apparently he/she/it came (but I didn´t see it happen)

These are all situations that may have happened, but you did not witness them personally, you were told, or read about it.

It is only like the English past perfect tense when it is combined with past tense

eg Dün okula gitmiştim, öğretmenim gelmedi.

I went (had gone) to school yesterday but my teacher did not come.

İki saat beklemiştik, .......... We had waited for 2 hours ........

Henry, your seven points are very helpful really, i got them thanks

but i will read the forum again to understand "miş + past simple" as in Abla´s example in the said forum

I understand everything now! Thanks everybody for help!!!!!!