The word "police" is only capitalized at the start of a sentence, or an exclamation ("Police!").
The militia were called out to help the police.
The correct spelling is join.An example sentence is "Paul plans to join the police".
No it should only be capitalized if it precedes a name.
No, police divisions such as robbery and homicide are not capitalized in the middle of a sentence unless they are part of a proper noun or title.
police sergeant.
Eg, "The police officer stood in the middle of the road, diverting traffic away from the accident."
I am in the middle of a sentence.
middle
The adjective in this sentence is police. The word police describes what kind of suit it was.
That is a simple, declarative sentence.
There were a lot of police at the demonstration.
3 if you spell sentence correct