it is / is it

Re: it is / is it


(1)

The first sentence needs another "that" to be correct.

If we say a question mark is "not required", does it mean that it is wrong to use it, or that it is optional?

This sentence is asking

If we say a question mark is "not required", does it mean

- that it is wrong to use it, or

- that it is optional?

Imagine removing the first part of the query, "that it is wrong to use it, or". The second part needs to make sense so a "that" is required.

(2)

The second sentence is correct -- it is slightly different in meaning -- it is asking

If we say a question mark is "not required", does it mean that it is wrong to use it, or is it (the case that it is) optional?

Thanks, Contrex, for your clear and detailed reply.

Best wishes.

That that is is that that is not is not that that is not is not that that is that that is is not that that is not is that not it it is.