Which sentence below shows correct use of em dashes?
In a-thousand-years, most of our greatest monuments such as they are will have crumbled to nothing.
In a thousand years, most of our greatest monuments – such as they are – will have crumbled to nothing.
In a thousand years, most of our greatest – monuments such as – they are will have crumbled to nothing.
In a thousand years, most of our greatest monuments such as they are will have crumbled-to-nothing.
Which sentence below shows correct use of em dashes?
In a-thousand-years, most of our greatest monuments such as they are will have crumbled to nothing.
In a thousand years, most of our greatest monuments – such as they are – will have crumbled to nothing.
In a thousand years, most of our greatest – monuments such as – they are will have crumbled to nothing.
In a thousand years, most of our greatest monuments such as they are will have crumbled-to-nothing.