quiet 、peaceful 、 tranquil 、 serene 、 halcyon均具有宁静的的意思。
相关例句：
1、我在宁静的宇宙飞船里踱步。
I paced in the peaceful spacecraft.
2、他们获得宁静的关键是把外噪音和内噪音都释放出来以消除压力。
They key to peacefulness is to let go of both outer and inner noise to eliminate stress.
3、干着这份工作，在那个宁静的小城我就有了非常舒适和悠闲的生活。
Having this job, I could have a very comfortable and relaxed life in that quiet city.