MD (Doctor of Medicine) and DO (Doctor of Osteopathic Medicine) are both fully licensed physicians in the U.S. MDs practice allopathic medicine, while DOs include a whole-person and musculoskeletal-focused approach called Osteopathic Manipulative Treatment (OMT). Both complete medical school, residency, licensing exams, and can work in any specialty.

The order of planets from the Sun is: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. This order is based on each planet's distance from the Sun, starting with the closest and ending with the farthest. Pluto is not included because it is classified as a dwarf planet

A simple sentence is a sentence that contains one independent clause with a subject and a verb, and it expresses a complete thought. It may include objects, modifiers, or phrases, but it has only one main clause. Example: The dog barked loudly.

A complex sentence is a sentence that contains one independent clause and at least one dependent clause. The dependent clause cannot stand alone and often begins with words like "because," "although," or "when." Example: Because it was raining, we stayed inside.

A compound sentence is a sentence made up of two independent clauses joined by a coordinating conjunction (like and, but, or) or a semicolon. Each clause can stand alone as a complete sentence. Example: I wanted to go for a walk, but it started raining.