Question about a letter in the Simplified manual

Just a quick question... In lesson 25, letter 227, something confuses me. There's an outline that I didn't recognise in the sentence "What's true of our personal lives is ____ true of our business relationships." I interpreted it at first as "usually", and I'm pretty sure that's what it's supposed to be (it's written as [use]-ly"), but I know that 'usually' is written as [usual]-e. In fact, I looked up what e-u-l-e means and it means "uselessly", which makes little sense in this context.

Is this a mis-write on the part of the author, or am I not interpreting it correctly?

Thanks :)

(by niftyboy1 for everyone)