TASK DEFINITION: In this task, you are given a sentence in the English language and your task is to convert it into the Japanese language. In translation, keep numbers as it is and make it sentence case (capitalize only the first word of each sentence and noun).
PROBLEM: With a population of 650,000, Montenegro is the world's newest country.

SOLUTION: 人口65万人のモンテネグロは、世界でもっとも新しい国である。

PROBLEM: According to Japan's Act on nationality, a non-Japanese child (under 20) who was after its birth legitimated by marriage and acknowledgment can acquire Japanese nationality by filing notification, with some requirements which the plaintiffs had already fulfilled.

SOLUTION: 日本の国籍法によると、結婚および認知によってその出生が合法化された日本人以外の子ども（二十歳以下）は、原告らが既に記入していた通知に記入することで日本国籍を得ることができる。

PROBLEM: British and American airline Virgin Atlantic has purchased six of these aeroplanes and intend to fit them with gyms and bars as well as seats.

SOLUTION:
イギリスとアメリカの航空会社であるヴァージンアトランティック航空はそれらの航空機を６機購入し、それらにシートだけではなくジムやバーを取り付けるつもりです。