European Languages

Difficult question
In my opinion, you can consider, French, German, Spanish or Russian
French: Besides France, French is the first language in many countires in
Africa
German: Many people in Eastern Europe know German
Spanish: People in South America speak Spanish. Also Portugese and Italian are similar to Spanish
Russian: It is not common in HK. But more and more people from Russia
like travelling. Maybe the tourist industries in HK need people who speak
Russian
So, at the end, up to you. Where do you want to work? in Afria, South
America......???

It really depends on your interest and/or your career path. If you talking about most countries offical language, then Spanish is your choice. If your career path is fasion field, you should consider to study French or Italian. If you want to be a interperter/translator, whatever language is fine.

歐洲語中以french同spainish最實用
因為法國同西班牙係舊時佔領殖物地較多既國家
兩者同屬拉丁語系
french普遍通行於非洲
而spainish則多用於南美一帶
另外spainish係全世界除英文外最多人用既語文
至於其他如Croatian / German / Greek / Italian / Macedonian / Polish / Russian / Ukrainian 等一般只適用於該國

Spanish 應會是最實用的‧很多落後國家都用portugese.這些國家的人多數唔識多國語言而Spaish and Portugese又很相似的‧所以Spanish 是最實用的‧