花园很宁静。

The garden is ___tranquil.

不幸的是，这个宁静的天堂却因不受控制的旅游业而逐年被毁。

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

她发现早晨的湖泊非常宁静。

She found the lake to be very ___tranquil in the morning.