a safe subject for discussion的用法和样例：
- A subject for discussion or analysis.
- The subject for discussion was the future of Rommel and his Africa Corps.
- It was mid-August and the subject for discussion was the future of Rommel and his African Corps.
- My father likes to bring up controversial subjects for discussion.
- The atmosphere must be a safe and supportive one for writers whose work-in-progress is up for discussion.