off the top of one's head englannista kaikille kielille

Kieli	Käännökset
espanja	de cabeza
ruotsi	på stående fot
saksa	aus dem Stegreif
suomi	suoralta kädeltä
venäjä	экспромтом (ekspromtom), навскидку (navskidku)

(idiomatic) In an extemporaneous manner; without careful thought, preparation, or investigation.

I cannot think of any good examples off the top of my head, but give me a couple of hours and I'm sure I could come up with something.

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