dumbfounded (adjective)

1. After his favorite cartoon character came to life, Tim was dumbfounded and unable to say a word.

2. When Sarah entered the candlelit room to find her partner down on one knee, she was dumbfounded and overcome with emotion.

3. The abstract painting left the critics dumbfounded, unable to comprehend its deeper meaning.

4. As the plot twist unfolded, the protagonist's dumbfounded expression mirrored the shock and surprise of the viewers.