In other threads I have noted problems compiling a file in Excel. I have survivied this difficulty, thankfully; but I don’t know how to print an Excel worksheet so that lines like those that appear on the screen, demiliting the cells’ content, show up on printed pages.
Or have I just overloooked a menu option or something like that? 
File
Page Setup
Sheet
click on Gridlines
missbunny is entirely correct.
If you wish to be more selective about which cells have visible borders, you have to use the Format > Cells > Border page.
Thanks to both. 
This is really something I should have puzzled out on my own… :o