# In C major, how might the use of A#sus2 → E major be described from a theory standpoint?

I have the progression

```C G Am G D G
```

then

```C G A#sus2  E F G Am
```

So this is suppose to be in C major from what I know the D is a secondary dominant since it resolves to the G(I suppose), but the A#sus2 and the E major is strange to me. So whats the theory behind this and how to apply them?

• @MatthewRead It's true that there aren't laws that dictate how chords can be used, but why do you think question is based on a premise that there are? He states some terminology that describes use of the D - isn't it fair to assume that he wants to know some terminology that could be used to describe the A#sus2 - E? (I do think the question could be clearer - e.g. if it included notation, or a link to a recording - but putting on hold as opinion-based doesn't seem to put us on a path gaining to that clarification) Commented May 27, 2017 at 7:13
• That A#sus 2 (probably better called Bbsus2) could be Fsus4, which brings it back into the 'key'.
– Tim
Commented May 27, 2017 at 11:04
• @MatthewRead - there are no laws; the OP is asking about theory, of which there's plenty.
– Tim
Commented May 27, 2017 at 11:06
• @MatthewRead Sorry for the inconvenience....what I wanted to know that if there's chord borrowing from a parallel mode or using secondary dominants...to what can we relate the A#sus2 or the E ? Commented May 27, 2017 at 17:54
• Though... if you ask specifically about ♭Ⅶ → Ⅲ... then this is not quite a duplicate. Commented May 27, 2017 at 23:41

These two chords are Bb (bVII) and E (V/vi) in C major, so on the surface that doesn't make much sense, but let's take a detour:

The Neapolitan is the major chord at the bII position in a key, and it's a predominant chord that resolves to the dominant (V). This N - V resolution is very common in minor key classic music. E.g in E minor you might hear F/A - B7 - Em. The verse of this Schoolhouse Rock tune is i - N - V - i.

The relative minor of C is A minor, and it turns out, Bb and E is a fine N - V resolution in A minor! Now in both A minor and C major the E would typically resolve to Am, but V to bVI (E to F) is a very common deceptive cadence.

In general, squeezing in progressions from the relative minor (or other nearby keys) is a great way to spice up major key music.

• That's a great observation, didn't occur to me! Commented May 27, 2017 at 23:44
• +1 This is exactly it, Steve! I wonder if you'd be interested in fleshing out this answer a little bit to make it more clear? Showing exactly what the Neapolitan and dominant are, and when they're "in" what key? Commented May 28, 2017 at 0:10
• There's something in this, although I don't think it addresses the question fully. The V/vi is all very well, but usually a secondary is followed by the target; not seeing that till 3 chords later.
– Tim
Commented May 28, 2017 at 9:59
• I prefer to think of it as a standard modal 'V--VI--VII--I' following the Neapolitan. Commented May 28, 2017 at 13:03
• @Richard See if my edit is an improvement Commented May 29, 2017 at 22:49