In this task, you are given two phrases: Head and Tail, separated with <sep>. The Head and the Tail events are short phrases possibly involving participants. The names of specific people have been replaced by generic words (e.g., PersonX, PersonY, PersonZ). PersonX is always the subject of the event. You have to determine whether the Head happens before the Tail or not. Classify your answers into "Yes" and "No". The phrase may also contain "___", a placeholder that can be an object, a person, and/or an action.

Example Input: Head: PersonX activates a shadow over everyone<sep>Tail: sit down
Example Output: No

Example Input: Head: PersonX sends photos with submission<sep>Tail: PersonX gets the photos back
Example Output: Yes

Example Input: Head: PersonX accidentally spilled ___<sep>Tail: to clean up the spill
Example Output:
No