Hi, everyone

I am now facing a problem of random ordering a list of sentences in
excel, I will be appreciate if anyone here can help me out.

The context is as this:

I have a list of sentences, from 1 to 200, each two of them are in
pair, thus, the 1st sentence belongs to class 1 and 2nd sentence
belongs to class 2, the 3rd sentence belongs to class 1, and the 4th
sentence belongs to class 2 and so on....(sentences with an odd
numbering belongs to class 1 and sentences with an even numbering
belongs to class 2).

My problem is that, I need to ask some people to classify these
sentences, but I do not want them to find out that, after several
pairs, they know already that the first sentence in the pair belongs
to class 1 and the second one belongs to class 2. Thus I need to
randomize the order of the sentences in the pair, say, in some pairs,
the order of the two sentences is reversed, and the pairs are randomly
choose. (So the people will not find out any rules)

After the person has done, I need to order the sentence into the
original ordering, together with the classification from the person,
thus I can know what will be the answer from the person.

I would be appreciate if anyone can tell me how to realize this? What
kind of functions should I use and how?

Many thanks in advance and hope to hear from you all......