21.  The first thing she noticed was the car park.

22.  The first thing that struck them was the color.

23.  The first thing that you should examine is the time out value set up in your PostScript printer driver.

24.  The first thing though was to get Nigel into some clean, dry clothes.

25.  The first thing to do is book a venue.

26.  The first thing to do is make a careful note of any error messages you get.

27.  The first thing to do is make sure the doors themselves are strong enough.

28.  The first thing to note about the preface is that it needs to be read.

29.  The first thing to realize is that it must consist in categorical imperatives, which are to be distinguished from hypothetical imperatives.