Verified answer

Nope. Czechs cannot understand Russian language. These two languages are quite distant without any common historical and cultural ties, and are not mutually understandable. Czech and Russian language have a ties in the old Slavonic language, from which both nations split away more than 1500 years ago and never again interacted with each other, except of four decades of the communism in the 20th century. This is very long time for any language to have mutually understandable conversation. Until the beginning of the 19th century, Czechs were not even aware of language association with Russia and Russians did not know that there is any Slavic speaking nation deep within Holy Roman Empire or Austrian monarchy. This association only became aware during Napoleonic wars when thousands of Russians were crossing through Bohemia and Moravia at that time. There are some funny historical observations from the Battle of Austerlitz in Moravia between Czech speaking population and Russians (they did not understand each other which made Russians extremely frustrated). While Czech, Slovak, and Russian are Slavic language, and share similar rule, behavior, and characteristic; vocabulary between Western and Eastern Slavic languages differs, and this make hard to engage meaningful conversation. Czechs and Slovaks are deeply influenced by Germanic and Latin vocabulary, and shared language development characteristic for the Western Europe. Some characters are language specific, and not pronounceable in others ř in Czech (no other Slavic has it and cannot pronounce it), ä in Slovak, and entire different alphabet in Russian.

Czech and Slovak are mutually understandable and readable, the grammar is behaving differently, and Czech and Slovak cannot write other language correctly without studying it first. Czechs can easily pick up Slovakism in the writings; last communist president of Czechoslovakia was Slovak and through his 20 years in power never learn Czech properly to the entertainment of the Czech masses. As with Czechs, Slovak language differ from Russians. There are however, sizable Rusinian nationality in eastern Slovakia, where people have language ties to Ukraine. This make Russian language better understandable in eastern Slovakia, but overall, the historical ties are similar like in Czech. Neither Czech or Slovak have ethnic boundary with Russia. Through the history, they did not share any ties to it. Czechs had own universities, written grammar, educated elite and leadership writing in their native language since medieval times, and certainly from 1350 onward. First translation of Bible in the Czech language happened in the 14th century and from 15th century, it was language used in university and schools instead of Latin and German. There was no need or way to interact with Old Slavonic or keep any association with eastern Slavic world.

Very very roughly I guess...

The languages are very different with only some words sounding similar. It could perhaps be enough to understand simple directions, but not to have a sensible conversation.

I am from Czech Republic and we understand ;) but not everything