die out 灭绝；消失；逐渐消失

【例句】
How did the dinosaurs die out?
恐龙是如何灭绝的？

However, with the new things becoming more and more popular, our traditional culture seems to become to die out.
然而在一昧求新的过程中，我们自己的传统文化却在逐渐消亡。