Answer:
Simple sentence
Step-by-step explanation:
The given sentence is a simple sentence. A simple sentence is a sentence that consists of one independent clause. An independent clause must contain a subject and predicate and express a complete thought. The sentence The moonlight spilled across the dark cemetery. meets these criteria.
A compound sentence consists of at least two independent clauses.
A complex sentence consists of one independent clause and at least one dependent clause.
A compound-complex sentence consists of at least two independent clauses and one or more dependent clauses.