The relevant idiomatic phrases are to put a FACE to suit the occasion, to put a good FACE on something, and to make a good/great FACE.
In terms of chronology, most face-based idiomatic expressions linked semantically to the conceptual category ATTITUDES are 20th century innovations, and these are found in numerous contemporary 20th - 21st century lexicographic works.
Here, compare the English idiomatic expression to pull/make/wear a long FACE with the French equivalent faire un visage long, allonger le VISAGE ('face'), Italian idiom avere il VISO ('face') lungo, fare la FACCIA ('face') lunga and the three German idioms ein langes GESICHT ('face') machen, ein langes GESICHT ('face') ziehen, mit einem langen GESICHT ('face') wieder abziehen (9) It seems that the idiomatic sense discussed here rests on the notion that long may imply 'sad', although long does not need to be overtly present in the structure of the phraseological formation.
It needs to be pointed out that some of the ATTITUDES-related idiomatic senses have counterparts in various European languages.
In order to avoid this, teachers should pay attention to the idiomatic performance of their pupils from the very beginning.
Let us understand that now we are in the sphere of primarily lexical idiomaticity, and therefore we refer to idiomatic expressions.
Generally though, we are convinced that there are no sharp, clear-cut boundaries between free combinations and idiomatic expressions, the latter category being represented by collocations and idioms proper.
The synchronic approach does not easily allow for an extreme view assuming that everything in language is idiomatic, and so learners will not know how to say it, or what it means, or whether it is a conventional thing to say, even if they know the grammar and the vocabulary of the language.