Breakdown of Судя по её осанке, она много танцует.
она
she / it (for a feminine noun)
много
a lot
танцевать
to dance
её
her (possessive)
Questions & Answers about Судя по её осанке, она много танцует.
Why is осанке in the Dative case?
It follows the preposition по, which takes the Dative case in this context. The set phrase судя по (judging by) is always followed by the Dative to indicate the evidence you are using to draw a conclusion.
Grammatically speaking, what kind of word is судя?
It is an imperfective verbal adverb (also called a gerund), formed from the verb судить (to judge). You might remember that verbal adverbs normally must share the same subject as the main verb. However, судя по has become a fixed expression, so it is perfectly fine to use it even though the main subject here is она (she) and she is not the one doing the judging.
Can осанка be used to describe any physical position?
No, осанка specifically refers to a person's carriage or bearing, meaning how straight they hold their back and shoulders. This is why it strongly hints at someone being a dancer. For a temporary physical position, you would use a word like поза.
Is the comma after осанке strictly required?
Yes. In Russian punctuation, phrases that begin with a verbal adverb (like судя) must always be separated from the rest of the sentence by commas, regardless of where they appear.