Unfortunately, though, this tranquil paradise has been destroyed year by year, by the uncontrolled tourism.

tranquil 来自拉丁语 tranquillus，意思是"平静的、安宁的"。这个词常用来形容环境或氛围的宁静祥和，比如平静的湖面、宁静的乡村等。在句中用来修饰"天堂"，强调这个地方原本平和安宁的状态。