22. The comma and period are used as in English. The colon is a point above the line (·) taking the place of our colon and semicolon. The mark of a direct question is (;), like our semicolon.
Meagan Ayer, ed. Goodell’s School Grammar of Attic Greek. Carlisle, Pennsylvania: Dickinson College Commentaries, 2018. ISBN: 978-1-947822-10-8.http://dcc.dickinson.edu/grammar/goodell/punctuation