None. Give those ones up. Start talking to people who understand that mis-communication happens. In my experience it is not only the choice of words that leads to trouble, cut also the attitudes which come with different cultures. It is very easy to assume things we grow up with as absolutes. It can often seem the people hold views that are absolutely outrageous, in our frame of reference, until you listen more & start to appreciate their starting point. When you listen more, you will find people you do not want to talk to more. Expect it. One answer is to stay of difficult topics, but then you will likely learn less. :( English has many ways to say things. So some of those ways are insulting. Few foreigners would understand not using "250" in China. It works both ways.

Talk about non controversial things first like the weather, your hobbies and what things you do every day. Good luck:)

I think Kevin's concept is a good one, but I think "radical" is a concept that must be judged from a cultural point of view. What is not radical to you, might be radical to another. Just as you bear in mind tolerance to maybe using the wrong word, tolerance to wrong topics or aspects, may be just as necessary. Other cultural perspectives can seem just plain nuts out of context.

You can try "What did I say?"

Most people (here, anyway) are quite tolerant toward non-native speakers because after all, it is not their native language. As long as you don't discuss any controversial issues and present a very radical view, you'll be fine. Speak politely with respect. That's all.