When you are a soldier, you should be a special soldier and be on the front line.
He is a front-line soldier in the army,
After retiring from the army, he joined the police force and became a criminal police officer. He was still on the front line.
The introduction is incompetent. If you like it, come in and take a look. If you don't, you can take a look.
This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.
