Provide examples of reduced relative clauses used in sentences.

Reduced relative clauses, also known as reduced adjective clauses or reduced adverbial clauses, are a shortened form of relative clauses that modify a noun or pronoun in a sentence. They are formed by omitting the relative pronoun (such as who, which, or that) and the verb "be" (am, is, are, was, were) from the relative clause. Here are some examples of reduced relative clauses used in sentences:

1. The girl standing over there is my sister. (reduced from "The girl who is standing over there is my sister.")
In this example, the relative pronoun "who" and the verb "is" have been omitted from the relative clause "who is standing over there."

2. The book written by J.K. Rowling is very popular. (reduced from "The book that is written by J.K. Rowling is very popular.")
Here, the relative pronoun "that" and the verb "is" have been omitted from the relative clause "that is written by J.K. Rowling."

3. The car parked outside belongs to my neighbor. (reduced from "The car that is parked outside belongs to my neighbor.")
In this sentence, the relative pronoun "that" and the verb "is" have been omitted from the relative clause "that is parked outside."

4. The man seen running in the park is a professional athlete. (reduced from "The man who is seen running in the park is a professional athlete.")
Here, the relative pronoun "who" and the verb "is" have been omitted from the relative clause "who is seen running in the park."

5. The house built in the 19th century has a lot of historical value. (reduced from "The house that was built in the 19th century has a lot of historical value.")
In this example, the relative pronoun "that" and the verb "was" have been omitted from the relative clause "that was built in the 19th century."

It is important to note that reduced relative clauses are only possible when the verb in the relative clause is in the present participle (-ing form) or past participle (-ed form).