Re: The Olympics, singluar or plural?
I agree with Raymott but I can't help but think that "The Olympics are an impressive event ..." is a very odd statement and begs the question "Do we follow it with "aren't they?" or "is it?""
We are left with the following possibilities:
The Olympics are impressive events, aren't they?
The Olympics are an impressive event, aren't they?
The Olympics is an impressive event, isn't it?
Some of the problem stems from the fact that the Olympic Games are made up of many individual events (sporting competitions, opening and closing ceremonies, medal ceremonies) but one single Olympic Games is an event in itself.
For the sake of simplicity, I would be inclined to say "The Olympics are impressive, aren't they?" and leave out the word "event" completely. That could, of course, be the grammatically cowardly way out.
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.