Both forms are correct, but mean different things!


  Not only is this true in this case, but ...


Means "This is true in this case. And somthing else. . ."


  Not only this is true in this case, but ...


Means "This is not the only thing that is true in this case, the other thing is. . ."

The problem is what the word "only" modifies. "Only" will modify the next word in the sentence, so if the next word is "is" then it means "is" is the only thing that the subject does, but if it modifies "this" it means the subject is unique.

Normally "this is true" is a statement, and "is this true" is a question. But when you need to modify "is", you run into this problem. English is full of strange exceptions like this one.

Question-like structure (word order) in non-question sentences
Is there a way to change the volume of the device? I've seen several apps do it. 

I have a desktop version of the iOS app and the device will be able to be controlled to some extent over the network. One of the things I want to allow the user to do is change the device volume and then play a sound. This can help if you loose your iPhone in a crack in your couch again, but can't find it. 

Is there any way that you can do this without Apple getting angry?
