General Decorum
Curse words should be avoided around children at all times. Some teens will curse in the streets however. Try not to confront them about it. Additionally, avoid any sort of discriminatory langauge, like those used to identify or describe the gay or transpeople, Blacks, or people with mental health issues, or learning handicaps. This is extremely offensive to most people and in incredibly bad taste.
Another important point on language is the continent, the country, and the people of the country.
In short, : Contenient: THE Americas, Country: United States of America, shortened to ¨America¨, Citizens: Americans (United Statesians does not exist in the English language, and is still too long, and sounds ackward.). The United States of Mexico is shortened to Mexico and its people to Mexicans; Those from the U.S. have the same right. So arguing about someone calling themselves ¨American¨ is calling for a full-on battle. Keep that comment to yourself unless you want a huge conflict to unravel.
General Decorum
Street harassment, that is, catcalling, trying to hit on a female as she is in public, often with an impolite tone and crude, rude, and/or demoralizing remarks, is considered in incredibly poor taste. There are some neighborhoods, mostly lower class, where street harassment is rather commonplace, it does not make it any less unacceptable. Women do not like it, so matter how many guys convince themselves otherwise. No one has ever walked home with a lady he catcalled or harassed on the streets. Women prefer respect.