我老了：

1. got a little bit of snow on the roof（字面含義為“屋頂有雪”，形容有白頭發(fā)）
2. I'm past it.
3. I'm over the hill.
4. I'm no spring chicken.（字面含義為“我不是春雞了”）
5. I'm not as young as I used to be.

不顯老：

1. Someone hasn't aged at all.
2. Someone looks very good for someone's age.