a deep discussion的用法和样例：
- A deep discussion on the advantage of flux-cored arc welding technology and the application on pressure vessel was made in this article, and some suggestion were put forward.
- The medieval town was fortified with a high wall and a deep moat.
- A deep gorge separates the two halves of the city.
- A deep ravine is on the left of the road.
- A deep melancholy runs through her poetry.