268.四次“灭亡”。die out，die off，die away，die down
（1）die out：指某个物种、习俗、观念等灭绝、绝迹。如：
Many species of birds have already died out.
许多种鸟类已经灭绝了。
（2）die off：指“一个一个地死去”（=die one by one）。如：
The trees along the river are dying off.
河岸的树木正在一棵棵的相继死去。
（3）die away：指某东西从视线中消失或声音、风、光线等渐息、渐弱。如：(https://www.daowen.com)
The plane in the sky died away.
天上的飞机渐渐地消失了。
（4）die down：意为“（慢慢）熄灭、平静下来”。如：
The fire is dying down.
火苗渐渐地熄灭了。
还有die of/from因……而死；die for为……而死。