Breakdown of Эти бриллианты подбросил кто-то из коллег.
этот
this [f: эта, n: это]
коллега
colleague
из
out of
кто-то
someone
Questions & Answers about Эти бриллианты подбросил кто-то из коллег.
Why is the subject кто-то из коллег at the very end of the sentence?
This demonstrates how Russian uses word order to show focus (Theme and Rheme). The known information (Эти бриллианты) goes at the beginning. The new, critical information (who planted them) goes at the very end. English often uses the passive voice to get this effect, while Russian simply rearranges the active sentence.
If Эти бриллианты is at the beginning, is it the subject?
No, Эти бриллианты is the direct object here, in the accusative case. For inanimate nouns, the plural nominative and accusative forms are identical. Because Russian word order is flexible, the object can easily sit at the start of the sentence to act as the theme or known context.
Why does the verb подбросил take a masculine singular ending when it refers to a group of colleagues?
How does the prefix in подбросил change the basic meaning of the verb?
The root verb is бросить (to throw). The prefix под- usually means under or approaching, but here it creates the specific meaning of secretly planting something, like fake evidence or contraband. You are figuratively throwing something under someone's radar.