Lost Sans Translation

There seems to be a trend in some television shows I see where people will speak in a language other than English. This occurs in several forms, all of which I enjoy and find daring. Lost is a great example of this, where lots of conversation occurs in other languages. In today's episode alone, all three of the following were used.

Form 1: Speakers use a foreign language, and subtitles are used to convey the meaning to the audience since there is little to no English in the scene.
Form 2: Speakers use a foreign language without subtitles, and then proceed to explain what was said, usually paraphrased, in English.
Form 3: Speakers use a foreign language without subtitles, and without any clarification afterwards. This one is used quite sparingly.

I couldn't make out all of the Russian, but she said at the end: Ти знаєш що мушеш робити. "You know what you must do." And yes, I know I wrote that in Ukrainian, it was just simpler that way for me.