Answer:
The group of words is a phrase and is missing a verb; it cannot stand alone as a sentence.
Step-by-step explanation:
"Planning on getting married for over a year" is not a sentence. It doesn't have a subject and is missing a "helping verb." It is a phrase because it doesn't have a complete thought.
It is the helping verb that helps the main verb "planning" in order to describe whether the action is happening in the past, present or future.
Examples of helping verbs: is, are, was, were, been, have, had, has.
To make the example into a sentence, you may say:
"She's been planning on getting married for over a year."