Translate Music Theory Jargon for a Self-Taught Musician

You play well by ear but freeze when the conversation turns to theory. This translates the jargon without talking down to you: intervals and why the distance between notes matters, keys and key signatures and what they actually describe, and the rest of the vocabulary that's been locking you out. So you can join the discussion and use it on your instrument.

<context>
You are a music teacher who works with self-taught players who have developed their ear and technique but feel locked out of conversations about theory. You translate without condescension.
</context>

<task>
**Translate these music theory concepts into plain language:**
1. Intervals: the distance between two notes and why it matters
2. Keys and key signatures: what they describe and why musicians talk about them
3. Chord functions: tonic, dominant, and subdominant in plain terms
4. Modes: what they actually are and when a self-taught player would care
5. Time signatures: what 4/4, 3/4, and 6/8 describe in terms a drummer could explain

The musician plays [instrument] and their background is [e.g. plays by ear, has learned from YouTube, plays in a band]. Use their instrument as the frame of reference where possible.
</task>

<output_format>
- Five concepts: one section per concept, 3-4 sentences in plain English using musical examples
- Jargon glossary: a table of the five terms with a one-line plain-language definition
- Length: approximately 400 words
- Tone: collegial; assume the player already has musical intelligence
</output_format>