housecarpenter

Yeah, Latin and Greek became somewhat more analytic during the time periods where a lot of foreign speakers were adopting them as their main languages. (That was during the Roman period, not the Middle Ages, for Latin; Latin in the Middle Ages was a dead language used only by learned people in non-everyday contexts, so its grammar was mostly preserved.) I don't know about Arabic.

A proof of a statement A may be valid in one formal system X but not capable of being written down in another formal system Y (and more strongly, there may be no proof at all that can be written down in Y that proves A or not-A, even if the statement A itself can be written down in Y).

It helps to be precise. Stating the incompleteness theorem imprecisely generally just makes people confused about what it could even mean. Strictly speaking, an incompleteness theorem has to be proven within a particular formal system X (the "meta-system"). It expresses--within X--that "for every consistent formal system Y expressible in X, there is a statement A expressible in Y such that there is no proof in Y of A or not-A". Here Y is the "object system".

The statement A is only unprovable within Y in particular. If it is expressible in X as well, it may be provable (or disprovable) within X. Indeed, one can trivially construct a formal system in which A is provable and which can express Y by adding A as an axiom to X.

The real, philosophically significant, non-particular-formal-system-specific import of the incompleteness theorem is not just that there are unprovable statements (which isn't really true, and is in fact kind of mathematically meaningless, outside of the context of a specific formal system, given that any statement or its negation can be taken as an axiom, and all we have to judge such choices is a non-mathematical notion of "self-evidency") but that (as the name suggests!) no formal system is complete--every formal system can express statements that it can't prove. It's all about that universal quantification.

Proto-Indo-European *dn̥ǵʰwéh₂s 'tongue' was feminine, hence why all the languages mentioned in this subthread (except Hebrew) have the word for 'tongue' feminine.

The consonants are the same, but whether the vowels are the same depends on your accent. In most British accents the vowel in 'lox' is fairly distinct from that in German 'lachs'. (Or I should probably say 'would be', since it's not a word known to most British English speakers.)