My motivation to learn English varies over the years. English study has been one of the three major courses for Chinese students for many years. We started English learning from junior high school, and the score to some extent determined our overall exam result. So at that time, it was more like a passive motivation(an indirect motivation); because I needed a good score, I learned. The first time I realized I wanted to learn English (for personal development) was after I had a job and I traveled abroad. I need to use it as a tool to help me better understand the world. My desire motivates me a lot. With constant learning, nowadays I can sometimes even realize the interesting points of the language. I think the joy of learning and practicability (practical application) is the motivation that can last a long time(that can sustain language learning for a long time). "Practicability" is correct but it is not very common.