When someone asks me if I speak Spanish I always say "Yes, but...." or "Sí, pero...." . I have spoken Spanish now for 30+ years and still put the "but" in there, as I know I have a US accent and make grammar mistakes. However, I also have other problems since I started traveling with my husband on his teaching trips. There is a variety of accent and vocabulary differences between areas of countries, but even more so between countries. For instance, what we called "patacones" ( a delicious snack made by frying and smashing and refrying plantains) in Colombia are called "tostones" in Puerto Rico and the Dominican Republic. To top it off, if I can't catch what is said to me I respond with "¿mande?" which is only used in Mexico to ask for clarification. Then I often get a look like "are you sure you speak Spanish?" and I start to wonder myself if I do.