What is a group of words that contains a subject and a predicate, expressing a complete thought?

A group of words that contains a subject and a predicate, expressing a complete thought, is a sentence. Sentences are fundamental components of writing that convey a complete idea or assertion. They can stand alone and provide a complete context to the reader.

In contrast, a phrase lacks a subject-verb pairing and does not express a complete thought. A clause, while it may contain both a subject and predicate, does not necessarily convey a complete thought unless it is an independent clause. A fragment is an incomplete sentence that does not express a full thought and typically is missing either a subject or a predicate. Therefore, the definition of a sentence aligns precisely with the requirement of containing both a subject and a predicate to deliver a complete message.