There is a big difference between learning a language in order to understand or to say something if needed, and wanting to acquire a second language in order to command it freely, almost like you command your first language, your mother tongue.
學習一門語言是為了理解或在需要時說些什麼,而想要學習第二語言是為了自由地掌握它,這兩者之間存在很大差異,就像你掌握你的第一語言,你的母語一樣。