子供(こども)のころ、よく公園(こうえん)で遊(あそ)びました。

This sentence talks about a past childhood memory, specifically the frequent activity of playing in a park during one's youth. It's a nostalgic way to share personal experiences from the past and what you used to do.

子供(こども)の時(とき)の思(おも)い出(で)、公園(こうえん)でよく遊(あそ)んだことを伝(つた)える表現(ひょうげん)です。