Complex sentence: A National Light is a term used to describe a lighthouse, lightvessel or other visual aid that is visible at night provided and maintainedby a governmental department or agency known as a General Lighthouse Authority for the purposes of navigation at sea and maritime safety.
Split into simpler sentences: A National Light is another name for a lighthouse, lightvessel or other visual aid that is visible at night. National lights are normally provided and maintained by a governmental department or agency known as a General Lighthouse Authority for the purposes of navigation at sea and maritime safety.