Plutarch, no. 1 is the corrected form of what WW was quoting, 2 & 3 what was asked for. 4 & 5 are quotes from Winnie Ille Pu, the Latin translation of the Milne classic. 4 is "You never can tell about elephants", 5 "You never can tell about footprints" (literally, "about elephants, footprints, it is always to be doubted").
The construction "disputandum, dubitandum" is called a gerund, q.v. in a dictionary or grammar.
I do not know about Latin roots in Russian, as I am not a Russian scholar; perhaps someone who is can respond to this. English has Latin words, phrases and other expressions which have been imported whole into the language, but not a direct connection. English was originally a Germanic language, expanded after the Norman Conquest with a vocabulary from Norman French, which, like other varieties of French, is a descendent of Latin.
The Romance Languages -- Italian, French, Spanish, Portuguese, Rumanian, and a variety of lesser-known languages such as Romansch, Catalan, Provençal et al. and their dialects and variants -- do not just have Latin roots; they are the descendants of Latin. That means that sometime after the 3rd century or so, regional variants began creeping into the Latin spoken all over the (then dying) Roman Empire. The process accelerated after the fall of the Empire, so that what used to be Latin spoken in what used to be Gaul was starting to evolve into what became French, of either the Lange d'Ouil (northern) variety or the Langue d'Oc (southern) variety; the Latin of Hibernia slowly turned into Spanish, etc.
Exactly how and when all these languages morphed from Latin into the Romance family of languages is not very clearly known, as it took place during the Dark Ages, which are so called because there are so few records of it. In the case of Italian and French, the process was virtually complete by the early 14th century, since what Dante, Bocaccio, and Villon wrote was Italian and French (archaic still, with some more modernization to come but comprehensible to speakers of modern Italian or French, like Elizabethan English is to us).
Late edit. Dr. Bill very kindly pointed out to me in a p.m. that I wrote Hibernia above when I meant Iberia. Chalk that up not to ignorance of geography but to getting old. Eheu fugaces! as the old Romans used to say. These golden years are not what they are cracked up to be. Made another error the same day in another post, which I'll have to fix.
