唯恐

例句：

1. 1. I am terrified of heights.
   我对高处感到恐惧。
2. 2. She was so frightened that she couldn't speak.
   她非常害怕以至于说不出话来。
3. 3. He is always fearful of the consequences of his actions.
   他总是担心自己行为的后果。