CQ World Wide Contest exchanges were randomly selected, which gave each exchange an equal probability of being selected. If you would like a slightly harder challenge, take a look at the non-Encore CQ World Wide Contest Exchanges, which select exchanges to be roughly proportional to recent participation for someone operating from North America and some types of exchanges are much more common than others.

For each exchange, try to head-copy it. First, the phrase is sent in Morse code. Then it is spoken. And finally, it is sent again in Morse code. If you missed something the first time when it was sent, the second time allows you an opportunity to learn it.

73 de AD0WE!