A — 4: and whether it finds sunken ships or old cities
B — 7: which is concerned only with ships and the history of seafaring
C — 6: that it is the study of archaeology done underwater
D — 3: that nearly every object made by humans
E — 5: that existed long before the invention of writing
F — 1: what those people were really like
Archaeology done underwater
Nautical archaeology is the science of finding, collecting, preserving, and studying human objects that have become lost or buried under water. It is a fairly modern field of study since it depends on having the technology to be able to remain underwater for some time to do real work. Whether it is conducted in freshwater or in the sea, __and whether it finds sunken ships or old cities__, nautical archaeology is another way of learning more about the human past.
Although some use the words nautical archaeology to mean a specialized branch of underwater archaeology, __which is concerned only with ships and the history of seafaring__, most consider the term to mean the same as the words underwater archaeology or marine archaeology. All of these interchangeable terms mean simply __that it is the study of archaeology done underwater__.
Once real trade began, it is safe to say __that nearly every object made by humans__ was probably transported over water at some point in time. By studying submerged objects, we can learn more about past human cultures. In fact, studying ancient artifacts is the only way to learn anything about human societies __that existed long before the invention of writing__. Being able to examine the actual objects made and used by ancient people not only adds to the written records they left behind, but allows us to get much closer to the reality of what life was like when they lived. Also, if we pay close attention to how the objects were made and used, we begin to get a more realistic picture of __what those people were really like__.