Literal translation
he makes mountains out of everything
Meaning
he makes a big deal out of everything
Explanation
This expression, almost identical in French, describes someone who systematically dramatises, turning every setback, however small, into an insurmountable obstacle. The literal image relies on the mountain, the geographical form par excellence of the massive, hard-to-cross, imposing obstacle: mentally building mountains where there are only small bumps means perceiving every difficulty at a scale wildly disproportionate to its reality. The word everything broadens the scope of the expression: it names a general disposition of character, applied indiscriminately to any subject whatsoever, well beyond any single circumstance. The link with fai d'uno mousco un tavan is immediate: both phrases belong to the same semantic family, that of exaggeration, though this one chooses a geographical register, stressing bulk and scale. The register is familiar, common, used both as affectionate reproach and as self-criticism.