What's the main difference between "practice" and "train?" Or are they interchangeable?

Native speaker’s answer
Rebecca
As a verb, to "practice" means to do an activity repetitively so as to improve your skills in it. It is quite similar in meaning to "train," which means to teach or learn a particular skill or activity over a period of time through practice and instruction. You can consider "train" to be maybe slightly more intensive an action. For athletes, "training" might be a better description of the intensive physical activity that they do daily. Ex: Athletes usually have to train everyday to stay in top physical condition. Ex: I have been practicing the guitar recently.