When a writer writes only subject or predicate and punctuates it as if were sentence the result is a?

This is a tricky situation! It's not exactly a grammatical sentence, but it depends on the context and intention:

1. Fragment: This is the most common and likely answer. A sentence fragment lacks either a subject or a predicate, and is therefore grammatically incomplete.

* Example: "Running." (Subject missing)

* Example: "Is very hungry." (Predicate missing)

2. Incomplete Sentence: This is similar to a fragment, but it implies a larger context where the missing part is understood.

* Example: "The red one." (Implies a preceding sentence like "Which shirt do you want?")

3. Deliberate Style: Sometimes, writers intentionally use fragments or incomplete sentences for artistic effect. This might be for emphasis, creating a sense of urgency, or mimicking natural speech.

* Example: "The storm. Raging." (For emphasis)

4. Title or Heading: A single word or phrase can function as a title or heading, even if it's not a complete sentence.

* Example: "Sunset." (Title)

In short: Without context, it's safest to call this a fragment. But depending on the situation, there might be other interpretations.