“square.” The Hebrew refers to a broad, open place. We would think of the city square. The Hebrew is plural, suggesting that she is all over the city at the various open places (for example, if the city had more than one gate there would be more than one broad plaza), not just close to home.
“at every corner.” One adulteress cannot be at every corner. The text is making the point that there are lots of wanton women, just as there are lots of immoral men. You can find trouble in lots of places if you go looking for it. The key is to want to maintain a godly walk and learning to avoid trouble.