men in blue的用法和样例：
- Police control the traffic in large cities.
- Mr.Green dressed up as a policeman in dark glasses.
- The captain's example incited the men to bravery.
- Some of the captains came in at the hawse-hole.
- Firemen reached the house on fire in time.
- At a signal,the fire men swarmed up the ropes.
- All the soldiers were cited for bravery in battle.
- We have several men named Xie in our squad.
- men in blue 警察