How can we translate the ettirgen edilgen clauses to English?

For example, the active form would be like this:

Ben sekretere mektubu yazdýrdým. This would be translated to: I had the secretary write the letter.

But what about: Mektup sekretere yazdýrýldý. How would this be translated?

Please help!

I would translate this as:

Ben sekretere mektubu yazdýrdým. I dictated the letter to the secretary.

Mektup sekretere yazdýrýldý. The letter was dictated to the secretary.

If you want to use the meaning of "have sb write sth", then perhaps the second sentence could be translated as: "The letter was made to be written by the secretary", which sounds a bit awkward, a better way to say it English would be to make the secretary the subject: "Secretary was made to write the letter."

Maybe this can help too

http://www.turkishclass.com/forumTitle_11068

Thanks for your explanation about Edilger and Ettirgen, really I have a lot of difficulties to understand it, moreover my mother tongue is Spanish not English.

Your examples are very clear except one of them:

I was stopped by someone

Ben durduruldum

I don´t understand this construccion, if the main verb is durmak, I was thinking about durulmak,

Thanks in advance for further explanations about this subject

Açıklamak için binlerce teşekkür ederim

The main verb isn´t durmak but durdurmak:

Durmak: to stop

Durdurmak: to make stop/bring to stop (someone)

Durdurulmak: to be stopped (by someone)

What confuses you in the verb dur(mak) is that it is an intransitive verb (English verb stop is both transitive and intransitive):

dur - stop (intransitive)

dinlenmek için durdum = I stopped to have a rest.

-ur is added to make it transitive:

durdur - stop (transitive)  

onu durduracak kimse yok = there is no one to stop him

its passive is durdurul = be stopped

polis tarafından durduruldum = I was stopped by the police

Hope this helps. If not, wait for advanced experts.