Scarborough Fair
Scarborough Fair is a very old English ballad, and it's the classic example of a tune in Dorian mode — a minor key with one note lifted. This is a traditional setting, in first position, in 3/4 (a slow waltz feel — one strong beat, two lighter).
The key: E Dorian
E Dorian is E natural minor with the 6th degree raised — C♯ instead of C. That one change makes the tune sound less mournful than plain minor, more open and wistful. Same key signature as G major and E minor (one sharp); the C♯ is written in as an accidental.
Phrase 1 — "Are you going to Scarborough Fair?"
Hear Dorian against plain minor
The same phrase with C natural — plain E natural minor:
Phrase 2 — "Parsley, sage, rosemary and thyme"
The usual mistake
Playing the C♯ flat, out of the habit that "it's a minor tune so the 6th should be low." In Dorian it's high — that's the point of the mode. Place it as a proper high 2nd finger, up against the 3rd. The other mistake: choppy separate notes. Scarborough Fair should sound like one long, unhurried breath per phrase.