I am learning by my own, using internet resources.
Sometimes it takes me a lot of time to understand a sentence, although I have some idea about the meaning. Here is an example:
Φω?ων μη δεξη κλοπιμην ανδ?ων πα?αθηκην αμφοτε?οι κλωπες, και ο δεξαμενος και ο κλεψας
(it is a sentence from Raphael Kühner, Greek Delectus, 1848, p.43 (60 in pdf reader)
My translation: Do not receive a stolen deposit from thievish people - both will be thieves, the giver and the receiver.
Thanks.