Ne zaman varacağınızı bize bildirin.
 - Let us know when you'll arrive.
Durumu görüşmek istiyorsanız, lütfen bize bildirin.
 - If you want to discuss the situation, please let us know.
I letcha do it.
... do all the time, so that when the moment comes, it can say, "I can't let you do that, Dave." ...
... the link, before we let you go there, we pop up this ...