Given the task definition and input, reply with output. In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.

A police dog , known in some English-speaking countries as a " K-9 " or " K9 " ( a homophone of " canine " ) , is a dog that is specifically trained to assist police and other law-enforcement personnel .

A police dog ( also called a K-9 ) is a dog trained to help police and other law enforcement people .