Which sentence type always has an implied subject?

The sentence type that always has an implied subject is an imperative sentence.

Here's why:

* Imperative sentences give commands or instructions.

* The implied subject is "you" (the person being addressed).

Example:

* "Close the door." (The implied subject is "you" - "You close the door.")

While the subject isn't explicitly stated, it's understood within the context of the command.