"Tim knows your book."
Translation:Тим знает вашу книгу.
How does "know" act upon your book, to put "your book" in the accusative? If Tim cut his finger, I could understand "cut" acting upon "his finger". But knowing a book ? How does one "know" upon the book?
Perhaps am not understanding the accusative case. From the notes, it seemed to be saying that the verb had to be acting upon the direct object. Can anyone help me be clear on this sentence? Thanks!
This is just how the verb "to know" works. Imagine a language being a theatre. The number of actors they have is limited, so different roles are performed by the same people. If the role does not seem to clearly stick to some archetype, the director just assigns it to the actor they think works best.
For «знать» and «понимать» the director seems to favour the Accusative. Admittedly, it is more obvious for more straightforward actions like "to take a book", "to give a book", "to write a book".
It might not work for a different verb or a different language, though, I think, most European languages will use "know" with Accusative (if they have cases at all). Nevertheless, the use of certain cases by participants, while oftentimes "making sense", is the property of a word meaning the action in the language; it is not an objective characteristic of the action itself.
"Tim cut his finger." What did Tim cut? His finger.
"Tim knows your book." The transitive verb know is not standing alone. What does Tim know? Your book. It doesnt really matter how.
"Tim works with me." What does Tim work? "Tim walks to the store." What does Tim walk? These sentences include intransitive verbs work and walk.
In Russian, the accusative case is used with transitive verbs.
It's not necessarily a verb "acting upon" something as rather the book is the direct object of the verb. The accusative case is used when words are in the direct object "slot" of a sentence. Tim knows what? Tim knows your book. Since "your book" is the direct object, "your book" needs to be accusative
Roughly (very roughly) speaking, Accusative is equivalent to "direct object", which does not use a preposition: I see a cat, you said words, we ate an apple, I love pizza, they play football, &c.
Now, dative case is roughly equivalent to indirect object (which needs a preposition in non-declined languages): I said so-and-so to mon, you gave a gift to her, the teacher read an article to his students.
(English in particular has a way to skipping prepositions in indirect objects, when in form of pronouns, that is remnant from dative case - so some examples might be phrased otherwise).
Consider as well that a single verb may have both a direct as well an indirect object: I said so-and-so (direct object/accusative) to somebody (indirect object/dative).
This equivalence doesn't work 100% of times, but it is a good start.
There are many free Russian keyboards apps and websites available, or you could buy a Russian keyboard, or you could configure your computer to switch between English and Russian input. They are already providing the free service of teaching you Russian, I'd say they're more than meeting you halfway.