忐忑不安

例句：

1. 1.She trembled as she heard the news.
   她听到这个消息时颤抖了一下。
2. 2.The old man was trembling with fear.
   老人因恐惧而颤抖。
3. 3. The baby was too young to understand the situation and started to tremble.
   婴儿太小，无法理解情况，开始发抖。