What made you want to learn how to speak cantonese in the first place? Is it common in Hong Kong to know both?
Japanese, Finnish, Icelandic, Arabic, Aramaic, and Old Norse. Those are my favorites. I'm a native English speaker, but I just don't care for English...
I've studied English, Greek, Spanish, French, German, Russian, & Mandarin. My two all time favorites are Mandarin & Greek!
English and slang are the two languages that I excel at... been known to "drop the F bomb" every now and then at the most inapproiate moment.