Meno has recalled Gorgias' two answers concerning virtues perfectly, but one gives many virtues, the other only one virtue, but not applicable to all. He is thus out of options which might satisfy Socrates' question, to say what that virtue is which is in all, and it is up to Socrates to keep the conversation on virtue going. He suggests that they go back and look at shape and shapes which had been mentioned a while ago. We should note that Socrates does not talk about shapes as such, but elements of shape (the round and the straight), just as numbers were discussed even earlier according to odd and even, not particular numbers, such as sixes or sevens.

Here I read through Platonic dialogues, translating and commenting on the Greek text as I go.

The resulting analyses may be found at:
https://theplatoparadigm.com

The full analyses include Euthyphro, Io, Hippias Minor, and Lysis, with extract/summaries from my books on Hippias Major, Meno, and Politeia (Republic)