I just read about it in a blog entry from an academic exchange institution, in that case, for Russian students. So, I came straight here to see whether someone had already written about it, and, as usual, I got surprised by the quantity and quality of the tips and information that are shared here in the Englishexperts website.
Very useful tip, I personally had never realised saying "how do you call it?" is logically incorrect. Thanks for sharing the tip Flávia.