Advanced Details: What are the 3 main sentence types in English?

Here is a chart comparing simple, compound, and complex sentence types based on their clause structure: 

Sentence Type Clause Structure

1. Simple 1 independent clause (a complete thought – it can stand alone without a connecting word).

Example : The engine started.

2. Compound 2 or more independent clauses joined by a conjunction (like "and," "but," "so") or a semicolon.

Example : Thanat was hungry, so he ate.

3. Complex 1 independent clause + 1 or more dependent clauses (a clause that cannot stand alone) joined by connecting words such as however, if, when, because.

Example : Although Sirilak was running late, she seemed relaxed.