This verse bears superficial similarities to 2 Nephi 5:7 and 11. In those verses Nephi describes in similarly terse words the foundation of his city. Here Alma’s record is similarly sparse. His people pitch their tents (as they did in 2 Nephi 5:7) and they begin to till the ground (as in 2 Nephi 5:11).
These people appear to assume that they will stay in this location. While they will eventually reunite with the people of Zarahemla, that is not on their minds at the moment. Now they are attempting to create their own city. When they have accomplished the most important tasks (immediate shelter in the way of tents, and the planting of crops for food) they turn to the task of building buildings. This suggests a desire for permanence. When Nephi’s people founded their city, the first mentioned building is a temple (2 Nephi 5:16). We do not know what the first building of Alma’s people was, but we might speculate that it was similarly religious, given the very obvious religious foundation of this new colony.
Textual: Both the printer’s manuscript and the 1830 edition of the Book of Mormon begin this text with “And it come to pass that they pitched….” This was removed beginning in 1837. Another more interesting deletion also occurs in this text. Not removed until 1920 was “began to build buildings &c” (Book of Mormon Critical Text. FARMS 1987. 2:473). The removal of the “&c” does not change the essential meaning of the text, but it is curious that it was there at all. The “&c” indicates that something else was built, but is non-specific. Any guess as to what was represented in the plate text is absolutely conjectural, but it is surprising for Mormon to generalize thus, unless the word being translated had a meaning of “build buildings and other evidences of civilization.” Such a hypothetical word might exist, and might be reasonably translated as “build buildings &c.”
The other possibility for the presence of “&c” is that Joseph or Oliver tired of writing something out, and simply abbreviated. The use of “&c” is typically for things that should be understood and therefore do not need saying. This second hypothesis would be quite surprising. It is hard to imagine translating so much of Isaiah where the text is identical to the KJV, and then abbreviating text about building a city. It would seem that the first possibility is the more likely. Certainly Mormon might have thought that the essentials of city establishment might warrant the “&c” even if we might wish for more elaboration.