Which group of americans fought under french command during world war i but did not have combat roles in the u. s. army?

The American Expeditionary Forces

Explanation:

The AEF - American Expeditionary Forces - was created on July 5th, 1917. The American Expeditionary Forces were initially aimed at transporting soldiers, equiment, ratios and supplies. The American Expeditionary Forces finally engaged in combat until October, 1917, when the First Division of the EAF fought from the trenches at Nancy, France. All of this under the French command  

definitely a for sure. ill see and update if i get the answer