Dummy subject
Does the sentence need a subject word that names nothing?
Kahulugan
A dummy subject is a word that fills the subject place in a sentence without naming anyone or anything. It lets a language build a full sentence even when there is no participant to name or the main content comes later. Some languages require such a word in weather or existence sentences; others can express these meanings without one. State and existence is about what is being said, not about a word filling the subject place. Words left out but understood covers meaningful words left unsaid; a dummy subject is present but names nothing.
Paano ito matukoy
Look for a subject word that does not point to a person or thing. Check whether it fills a required grammatical place rather than referring back to something or pointing to a place.