People have already added some great advice for your Japanese' sake, so I'm going to only chip in what I've learned myself.
It astonishes me that people grow to simply learn the "native word/sound -- foreign word/sound", while language is so much more than that. If one's own language is capable of producing words of similar meanings around the same subject, why do we assume that foreign ones lack it? So, learn the meaning. Learn what makes this idea of a thing this and not something else, and what other ideas of a thing there, and in what contexts can and shouldn't you use this particular idea. This is an important part of any language that people are missing for some odd reason.