I was surprised and became sad.
- Je fus surpris et devins triste.
Seeing that you're not surprised, I think you must have known.
- Vu que tu n'es pas surpris, je pense que tu étais au courant.
I was amazed at his courage.
- Son courage m'a surprise.
Everybody was startled.
- Tout le monde a été surpris.
Tom was startled by a knock on the door.
- Tom a été surpris par un coup sur la porte.