You can download a Belgian infantry manuel from 1932 here:
http://www.abbl1940.be/ABBL1940files/AB ... ameset.htm
It is in Dutch however. I have read it. It looks pretty standard for a West-European country. There is a lot aboout marksmanship but it also says that the most powerful weapon of the infantry (groupe) squad is the LMG.
There is a big piece about fire and movement, using cover in the advance, covering fire etc. Digging in and building obstacles and fortifications is another important chapter, with a picture. There is a text about working together with the mobile cavalry and bicycle troops, the artillery, engineers and the Renault FT17 tanks (no longer used in 1940).
One thing that i noticed is that there is almost nothing about fighting in villages or cities.