Final answer:
The sentence "After the groundhog sees its shadow, it returns to its burrow until spring" is a simple sentence, characterized by a single independent clause with a subject and a verb that expresses a complete thought.
Step-by-step explanation:
The question you've asked, "After the groundhog sees its shadow, it returns to its burrow until spring. What type of sentence is this?", requires an understanding of sentence types. This sentence is a simple sentence because it has one independent clause and no dependent clauses. An independent clause is a group of words that can stand alone as a sentence - it contains both a subject and a verb and expresses a complete thought.
In the example in question, the subject is 'the groundhog' and the verb is 'returns'. Since the sentence contains a single subject and verb pair and expresses a complete thought, it qualifies as a simple sentence. It should also be noted that the grammatical term 'simple sentence' does not reflect the complexity of the information within the sentence, but rather the structure of the sentence itself.
It is important to ensure proper punctuation and clarity of expression to avoid issues such as comma splices, which occur when two independent clauses are incorrectly joined by a comma without a coordinating conjunction. Understanding the types of sentences and proper punctuation contributes to stronger writing skills and clearer communication.