The Wehrmacht soldiers are the grunts of the Nazi Army. They are the most easier enemies and are encountered in the greatest numbers, and will use that to their advantage. They will stick to machine gun nests, and when B.J kills the one manning it, another will move in his place. Wehrmacht soldiers individually aren't much of a threat, they fall quickly to every weapon. Wehrmacht officers present can direct soldiers into battle. Dealing with them "en masse" usually means taking a few out at a time. Using the MP 40 is a good choice, as the Wehrmacht soldiers tend to use it. On extremely rare occassion, they are found using Panzerschrecks.
See: Wolfenstein (2009)