How come

• It’s a grammatical shortcut that English adopted because it’s efficient and carries a specific conversational nuance.
• “How come”-questions don’t require subject-verb inversion.
  • Normal Question (with inversion):** “Why are you so dirty?”
  • “How Come” Question (no inversion): “How come you are so dirty?” (Same word order as the statement: “You are so dirty.”)
  • Reason: “How come” is a shortened, colloquial form of “How did it come about that…” or “How comes it that…”. Over time, the phrase got shortened and fossilized into the fixed expression.
    • “How come you are so dirty?”
    • “How did it come about that you are so dirty?”
      • inversion happens in the first clause (“How did it come…”).
• Differences from “Why”:
  • Inversion:
    • “Why”: with inversion (unless the subject is a question word itself).
      • Why is she late?
    • “How come”: no inversion.
      • How come she is late?
  • Usage/Tone:
    • “How come”:
      • more informal
      • often shows surprise, skepticism, or a request for an explanation that the speaker finds puzzling