Breakdown of Судя по почерку, это писал врач.
это
this / it is
врач
doctor
писать
to write
судя по
judging by
Questions & Answers about Судя по почерку, это писал врач.
Why does почерку end in -у here?
It is in the Dative case, triggered by the preposition по. The phrase судя по (judging by) always requires the Dative case for the evidence you are observing.
What exactly is the word судя?
It is an adverbial participle (often called a verbal adverb) formed from the imperfective verb судить (to judge). It translates directly to the '-ing' form in English: 'judging'.
Why is the sentence ordered as это писал врач instead of врач писал это?
Russian typically places the most important new information (the sentence focus) at the end of the clause. Since the main revelation or punchline here is that a doctor is the author, врач goes last.
Why use the imperfective verb писал instead of the perfective написал for a completed text?
When focusing on identifying the author or creator of something rather than the completion of the action itself, Russian prefers the imperfective aspect. You are pointing out who was engaged in the process of writing this.